blocks|key|1253967|text|​|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1253968|<HTML>
++<HEAD>
++++<SCRIPT+language=Javascript>
+++++++
++++</SCRIPT>
++</HEAD>
++<BODY>
++++<INPUT+id="txtChar"+onkeypress="return+isNumberKey(event)"+
+++++++++++type="text"+name="txtChar">
++</BODY>
</HTML>|code-block|syntax|javascript|1253969|1253970|这真的很有效！|1253971|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|M|8|@]|9|@]|A|$E|F]]|$1|G|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|O|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|P|8|@]|9|@]|A|$]]]|K|$]]

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;HTML&gt;
  &lt;HEAD&gt;
    &lt;SCRIPT language=Javascript&gt;
       &lt;!--
       function isNumberKey(evt)
       {
          var charCode = (evt.which) ? evt.which : evt.keyCode;
          if (charCode != 46 &amp;&amp; charCode &gt; 31 
            &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
             return false;

          return true;
       }
       //--&gt;
    &lt;/SCRIPT&gt;
  &lt;/HEAD&gt;
  &lt;BODY&gt;
    &lt;INPUT id="txtChar" onkeypress="return isNumberKey(event)" 
           type="text" name="txtChar"&gt;
  &lt;/BODY&gt;
&lt;/HTML&gt;</code></pre>
</div>
</div>
</p>

<p>This really works!</p>


blocks|key|1039543|text|接受的解决方案不完整，因为您可以输入多个'.'，例如24..22..22。通过一些小的修改，它将像预期的那样工作：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039544|​|1039545|<html>

<head>
++<script+type="text/javascript">
++++function+isNumberKey(txt,+evt)+{
++++++var+charCode+=+(evt.which)+?+evt.which+:+evt.keyCode;
++++++if+(charCode+==+46)+{
++++++++//Check+if+the+text+already+contains+the+.+character
++++++++if+(txt.value.indexOf('.')+===+-1)+{
++++++++++return+true;
++++++++}+else+{
++++++++++return+false;
++++++++}
++++++}+else+{
++++++++if+(charCode+>+31+&&
++++++++++(charCode+<+48+%7C%7C+charCode+>+57))
++++++++++return+false;
++++++}
++++++return+true;
++++}
++</script>
</head>

<body>
++<input+type="text"+onkeypress="return+isNumberKey(this,+event);"+/>
</body>

</html>|code-block|syntax|javascript|1039546|1039547|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|N|8|@]|9|@]|A|$G|H]]|$1|I|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|P|8|@]|9|@]|A|$]]]|K|$]]

<p>The accepted solution is not complete, since you can enter multiple '.', for example 24....22..22. with some small modifications it will work as intended:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;html&gt;

&lt;head&gt;
  &lt;script type="text/javascript"&gt;
    function isNumberKey(txt, evt) {
      var charCode = (evt.which) ? evt.which : evt.keyCode;
      if (charCode == 46) {
        //Check if the text already contains the . character
        if (txt.value.indexOf('.') === -1) {
          return true;
        } else {
          return false;
        }
      } else {
        if (charCode &gt; 31 &amp;&amp;
          (charCode &lt; 48 || charCode &gt; 57))
          return false;
      }
      return true;
    }
  &lt;/script&gt;
&lt;/head&gt;

&lt;body&gt;
  &lt;input type="text" onkeypress="return isNumberKey(this, event);" /&gt;
&lt;/body&gt;

&lt;/html&gt;</code></pre>
</div>
</div>
</p>


blocks|key|1038947|text|form.onsubmit+=+function(){
++++return+textarea.value.match(/%5E\d%2B(\.\d%2B)?$/);
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1038948|这就是你要找的吗？|unstyled|1038949|我希望它能帮上忙。|1038950|编辑:我对上面的示例进行了编辑，使其只能有一个句点，前面至少有一个数字，后面至少有一个数字。|1038951|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|N|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|F|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|F|7|Q|8|@]|9|@]|A|$]]]|L|$]]

<pre><code>form.onsubmit = function(){
    return textarea.value.match(/^\d+(\.\d+)?$/);
}
</code></pre>

<p>Is this what you're looking for?</p>

<p>I hope it helps.</p>

<p>EDIT: I edited my example above so that there can only be one period, preceded by at least one digit and followed by at least one digit.</p>


blocks|key|1254581|text|这是另一个解决方案，它允许使用小数，并将小数后的位数限制为2位小数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1254582|​|1254583|function+isNumberKey(evt,+element)+{
++var+charCode+=+(evt.which)+?+evt.which+:+event.keyCode
++if+(charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57)+&&+!(charCode+==+46+%7C%7C+charCode+==+8))
++++return+false;
++else+{
++++var+len+=+$(element).val().length;
++++var+index+=+$(element).val().indexOf('.');
++++if+(index+>+0+&&+charCode+==+46)+{
++++++return+false;
++++}
++++if+(index+>+0)+{
++++++var+CharAfterdot+=+(len+%2B+1)+-+index;
++++++if+(CharAfterdot+>+3)+{
++++++++return+false;
++++++}
++++}

++}
++return+true;
}|code-block|syntax|javascript|1254584|<script+src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input+type="number"+id="rate"+placeholder="Billing+Rate"+required+onkeypress="return+isNumberKey(event,this)">|1254585|1254586|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|P|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|K|3|C|5|6|7|R|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|M|$]]

<p>Here is one more solution which allows for decimal numbers and also limits the digits after decimal to 2 decimal places.</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="false" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>function isNumberKey(evt, element) {
  var charCode = (evt.which) ? evt.which : event.keyCode
  if (charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57) &amp;&amp; !(charCode == 46 || charCode == 8))
    return false;
  else {
    var len = $(element).val().length;
    var index = $(element).val().indexOf('.');
    if (index &gt; 0 &amp;&amp; charCode == 46) {
      return false;
    }
    if (index &gt; 0) {
      var CharAfterdot = (len + 1) - index;
      if (CharAfterdot &gt; 3) {
        return false;
      }
    }

  }
  return true;
}</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"&gt;&lt;/script&gt;
&lt;input type="number" id="rate" placeholder="Billing Rate" required onkeypress="return isNumberKey(event,this)"&gt;</code></pre>
</div>
</div>
</p>


blocks|key|1040187|text|这里提供的所有解决方案都使用单键事件。这很容易出错，因为输入也可以使用copy‘n’粘贴或drag‘n’drag。此外，一些解决方案限制非字符键的使用，如ctrl%2Bc、Pos1等。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1040188|我建议你检查结果是否符合你的期望，而不是检查每一个按键。|1040189|​|1040190|var+validNumber+=+new+RegExp(/%5E\d*\.?\d*$/);
var+lastValid+=+document.getElementById("test1").value;
function+validateNumber(elem)+{
++if+(validNumber.test(elem.value))+{
++++lastValid+=+elem.value;
++}+else+{
++++elem.value+=+lastValid;
++}
}|code-block|syntax|javascript|1040191|<textarea+id="test1"+oninput="validateNumber(this);"+></textarea>|1040192|1040193|oninput事件是在文本区域中的内容发生更改之后、呈现之前触发的。|1040194|您可以将RegEx扩展为您想要接受的任何数字格式。与检查单个按键相比，这要容易维护和扩展得多。|1040195|entityMap^0|25|6|2C|4|0|0|0|0|0|0|0|7|0|0^^$0|@$1|2|3|4|5|6|7|X|8|@$9|Y|A|Z|B|C]|$9|10|A|11|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|12|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|13|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|14|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|L|7|15|8|@]|D|@]|E|$M|N]]|$1|Q|3|I|5|6|7|16|8|@]|D|@]|E|$]]|$1|R|3|S|5|6|7|17|8|@$9|18|A|19|B|C]]|D|@]|E|$]]|$1|T|3|U|5|6|7|1A|8|@]|D|@]|E|$]]|$1|V|3|-4|5|6|7|1B|8|@]|D|@]|E|$]]]|W|$]]

<p>All solutions presented here are using single key events. This is very error prone since input can be also given using copy'n'paste or drag'n'drop. Also some of the solutions restrict the usage of non-character keys like <code>ctrl+c</code>, <code>Pos1</code> etc.</p>

<p>I suggest rather than checking every key press you check whether the result is valid in respect to your expectations.</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>var validNumber = new RegExp(/^\d*\.?\d*$/);
var lastValid = document.getElementById("test1").value;
function validateNumber(elem) {
  if (validNumber.test(elem.value)) {
    lastValid = elem.value;
  } else {
    elem.value = lastValid;
  }
}</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;textarea id="test1" oninput="validateNumber(this);" &gt;&lt;/textarea&gt;</code></pre>
</div>
</div>
</p>

<p>The <code>oninput</code> event is triggered just after something was changed in the text area and before being rendered.</p>

<p>You can extend the RegEx to whatever number format you want to accept. This is far more maintainable and extendible than checking for single key presses.</p>


blocks|key|1038957|text|你在找这样的东西吗？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1038958|+++<HTML>
+++<HEAD>
+++<SCRIPT+language=Javascript>
++++++
+++</SCRIPT>
+++</HEAD>
+++<BODY>
++++++<INPUT+id="txtChar"+onkeypress="return+isNumberKey(event)"+type="text"+name="txtChar">
+++</BODY>
++</HTML>|code-block|syntax|javascript|1038959|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>Are you looking for something like this?</p>

<pre><code>   &lt;HTML&gt;
   &lt;HEAD&gt;
   &lt;SCRIPT language=Javascript&gt;
      &lt;!--
      function isNumberKey(evt)
      {
         var charCode = (evt.which) ? evt.which : event.keyCode
         if (charCode != 46 &amp;&amp; charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
            return false;

         return true;
      }
      //--&gt;
   &lt;/SCRIPT&gt;
   &lt;/HEAD&gt;
   &lt;BODY&gt;
      &lt;INPUT id="txtChar" onkeypress="return isNumberKey(event)" type="text" name="txtChar"&gt;
   &lt;/BODY&gt;
  &lt;/HTML&gt;
</code></pre>


blocks|key|1039374|text|只需在Jquery中应用此方法，您就可以验证您的textbox，使其只接受带有小数的数字。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039375|function+IsFloatOnly(element)+{++++
var+value+=+$(element).val();+
var+regExp+="%5E\\d%2B(\\.\\d%2B)?$";
return+value.match(regExp);+
}|code-block|syntax|javascript|1039376|请参阅工作演示here|offset|length|1039377|entityMap|0|LINK|mutability|MUTABLE|url|http://jsbin.com/ImIruPEf/3/edit^0|0|0|7|4|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

<p>Just need to apply this method in Jquery and you can validate your textbox to just accept number with a decimal only.</p>

<pre><code>function IsFloatOnly(element) {    
var value = $(element).val(); 
var regExp ="^\\d+(\\.\\d+)?$";
return value.match(regExp); 
}
</code></pre>

<p>Please see working demo <a href="http://jsbin.com/ImIruPEf/3/edit" rel="nofollow">here</a></p>


blocks|key|1254012|text|以下是可以帮助您脚本：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1254013|<script+type="text/javascript">
//+price+text-box+allow+numeric+and+allow+2+decimal+points+only
function+extractNumber(obj,+decimalPlaces,+allowNegative)
{
++++var+temp+=+obj.value;

++++//+avoid+changing+things+if+already+formatted+correctly
++++var+reg0Str+=+'[0-9]*';
++++if+(decimalPlaces+>+0)+{
++++++++reg0Str+%2B=+'\[\,\.]?[0-9]{0,'+%2B+decimalPlaces+%2B+'}';
++++}+else+if+(decimalPlaces+<+0)+{
++++++++reg0Str+%2B=+'\[\,\.]?[0-9]*';
++++}
++++reg0Str+=+allowNegative+?+'%5E-?'+%2B+reg0Str+:+'%5E'+%2B+reg0Str;
++++reg0Str+=+reg0Str+%2B+'$';
++++var+reg0+=+new+RegExp(reg0Str);
++++if+(reg0.test(temp))+return+true;

++++//+first+replace+all+non+numbers
++++var+reg1Str+=+'[%5E0-9'+%2B+(decimalPlaces+!=+0+?+'.'+:+'')+%2B+(decimalPlaces+!=+0+?+','+:+'')+%2B+(allowNegative+?+'-'+:+'')+%2B+']';
++++var+reg1+=+new+RegExp(reg1Str,+'g');
++++temp+=+temp.replace(reg1,+'');

++++if+(allowNegative)+{
++++++++//+replace+extra+negative
++++++++var+hasNegative+=+temp.length+>+0+&&+temp.charAt(0)+==+'-';
++++++++var+reg2+=+/-/g;
++++++++temp+=+temp.replace(reg2,+'');
++++++++if+(hasNegative)+temp+=+'-'+%2B+temp;
++++}

++++if+(decimalPlaces+!=+0)+{
++++++++var+reg3+=+/[\,\.]/g;
++++++++var+reg3Array+=+reg3.exec(temp);
++++++++if+(reg3Array+!=+null)+{
++++++++++++//+keep+only+first+occurrence+of+.
++++++++++++//++and+the+number+of+places+specified+by+decimalPlaces+or+the+entire+string+if+decimalPlaces+<+0
++++++++++++var+reg3Right+=+temp.substring(reg3Array.index+%2B+reg3Array[0].length);
++++++++++++reg3Right+=+reg3Right.replace(reg3,+'');
++++++++++++reg3Right+=+decimalPlaces+>+0+?+reg3Right.substring(0,+decimalPlaces)+:+reg3Right;
++++++++++++temp+=+temp.substring(0,reg3Array.index)+%2B+'.'+%2B+reg3Right;
++++++++}
++++}

++++obj.value+=+temp;
}
function+blockNonNumbers(obj,+e,+allowDecimal,+allowNegative)
{
++++var+key;
++++var+isCtrl+=+false;
++++var+keychar;
++++var+reg;
++++if(window.event)+{
++++++++key+=+e.keyCode;
++++++++isCtrl+=+window.event.ctrlKey
++++}
++++else+if(e.which)+{
++++++++key+=+e.which;
++++++++isCtrl+=+e.ctrlKey;
++++}

++++if+(isNaN(key))+return+true;

++++keychar+=+String.fromCharCode(key);

++++//+check+for+backspace+or+delete,+or+if+Ctrl+was+pressed
++++if+(key+==+8+%7C%7C+isCtrl)
++++{
++++++++return+true;
++++}

++++reg+=+/\d/;
++++var+isFirstN+=+allowNegative+?+keychar+==+'-'+&&+obj.value.indexOf('-')+==+-1+:+false;
++++var+isFirstD+=+allowDecimal+?+keychar+==+'.'+&&+obj.value.indexOf('.')+==+-1+:+false;
++++var+isFirstC+=+allowDecimal+?+keychar+==+','+&&+obj.value.indexOf(',')+==+-1+:+false;
++++return+isFirstN+%7C%7C+isFirstD+%7C%7C+isFirstC+%7C%7C+reg.test(keychar);
}
function+blockInvalid(obj)
{
++++var+temp=obj.value;
++++if(temp=="-")
++++{
++++++++temp="";
++++}

++++if+(temp.indexOf(".")==temp.length-1+&&+temp.indexOf(".")!=-1)
++++{
++++++++temp=temp%2B"00";
++++}
++++if+(temp.indexOf(".")==0)
++++{
++++++++temp="0"%2Btemp;
++++}
++++if+(temp.indexOf(".")==1+&&+temp.indexOf("-")==0)
++++{
++++++++temp=temp.replace("-","-0")+;
++++}
++++if+(temp.indexOf(",")==temp.length-1+&&+temp.indexOf(",")!=-1)
++++{
++++++++temp=temp%2B"00";
++++}
++++if+(temp.indexOf(",")==0)
++++{
++++++++temp="0"%2Btemp;
++++}
++++if+(temp.indexOf(",")==1+&&+temp.indexOf("-")==0)
++++{
++++++++temp=temp.replace("-","-0")+;
++++}
++++temp=temp.replace(",",".")+;
++++obj.value=temp;
}
//+end+of+price+text-box+allow+numeric+and+allow+2+decimal+points+only
</script>

<input+type="Text"+id="id"+value=""+onblur="extractNumber(this,2,true);blockInvalid(this);"+onkeyup="extractNumber(this,2,true);"+onkeypress="return+blockNonNumbers(this,+event,+true,+true);">|code-block|syntax|javascript|1254014|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>here is script that cas help you :</p>

<pre><code>&lt;script type="text/javascript"&gt;
// price text-box allow numeric and allow 2 decimal points only
function extractNumber(obj, decimalPlaces, allowNegative)
{
    var temp = obj.value;

    // avoid changing things if already formatted correctly
    var reg0Str = '[0-9]*';
    if (decimalPlaces &gt; 0) {
        reg0Str += '\[\,\.]?[0-9]{0,' + decimalPlaces + '}';
    } else if (decimalPlaces &lt; 0) {
        reg0Str += '\[\,\.]?[0-9]*';
    }
    reg0Str = allowNegative ? '^-?' + reg0Str : '^' + reg0Str;
    reg0Str = reg0Str + '$';
    var reg0 = new RegExp(reg0Str);
    if (reg0.test(temp)) return true;

    // first replace all non numbers
    var reg1Str = '[^0-9' + (decimalPlaces != 0 ? '.' : '') + (decimalPlaces != 0 ? ',' : '') + (allowNegative ? '-' : '') + ']';
    var reg1 = new RegExp(reg1Str, 'g');
    temp = temp.replace(reg1, '');

    if (allowNegative) {
        // replace extra negative
        var hasNegative = temp.length &gt; 0 &amp;&amp; temp.charAt(0) == '-';
        var reg2 = /-/g;
        temp = temp.replace(reg2, '');
        if (hasNegative) temp = '-' + temp;
    }

    if (decimalPlaces != 0) {
        var reg3 = /[\,\.]/g;
        var reg3Array = reg3.exec(temp);
        if (reg3Array != null) {
            // keep only first occurrence of .
            //  and the number of places specified by decimalPlaces or the entire string if decimalPlaces &lt; 0
            var reg3Right = temp.substring(reg3Array.index + reg3Array[0].length);
            reg3Right = reg3Right.replace(reg3, '');
            reg3Right = decimalPlaces &gt; 0 ? reg3Right.substring(0, decimalPlaces) : reg3Right;
            temp = temp.substring(0,reg3Array.index) + '.' + reg3Right;
        }
    }

    obj.value = temp;
}
function blockNonNumbers(obj, e, allowDecimal, allowNegative)
{
    var key;
    var isCtrl = false;
    var keychar;
    var reg;
    if(window.event) {
        key = e.keyCode;
        isCtrl = window.event.ctrlKey
    }
    else if(e.which) {
        key = e.which;
        isCtrl = e.ctrlKey;
    }

    if (isNaN(key)) return true;

    keychar = String.fromCharCode(key);

    // check for backspace or delete, or if Ctrl was pressed
    if (key == 8 || isCtrl)
    {
        return true;
    }

    reg = /\d/;
    var isFirstN = allowNegative ? keychar == '-' &amp;&amp; obj.value.indexOf('-') == -1 : false;
    var isFirstD = allowDecimal ? keychar == '.' &amp;&amp; obj.value.indexOf('.') == -1 : false;
    var isFirstC = allowDecimal ? keychar == ',' &amp;&amp; obj.value.indexOf(',') == -1 : false;
    return isFirstN || isFirstD || isFirstC || reg.test(keychar);
}
function blockInvalid(obj)
{
    var temp=obj.value;
    if(temp=="-")
    {
        temp="";
    }

    if (temp.indexOf(".")==temp.length-1 &amp;&amp; temp.indexOf(".")!=-1)
    {
        temp=temp+"00";
    }
    if (temp.indexOf(".")==0)
    {
        temp="0"+temp;
    }
    if (temp.indexOf(".")==1 &amp;&amp; temp.indexOf("-")==0)
    {
        temp=temp.replace("-","-0") ;
    }
    if (temp.indexOf(",")==temp.length-1 &amp;&amp; temp.indexOf(",")!=-1)
    {
        temp=temp+"00";
    }
    if (temp.indexOf(",")==0)
    {
        temp="0"+temp;
    }
    if (temp.indexOf(",")==1 &amp;&amp; temp.indexOf("-")==0)
    {
        temp=temp.replace("-","-0") ;
    }
    temp=temp.replace(",",".") ;
    obj.value=temp;
}
// end of price text-box allow numeric and allow 2 decimal points only
&lt;/script&gt;

&lt;input type="Text" id="id" value="" onblur="extractNumber(this,2,true);blockInvalid(this);" onkeyup="extractNumber(this,2,true);" onkeypress="return blockNonNumbers(this, event, true, true);"&gt;
</code></pre>


blocks|key|1039262|text|对于像我一样在这里跌跌撞撞的人，这里有一个我写的jQuery+1.10.2版本，它对我来说工作得很好，尽管需要大量的资源：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039263|/***************************************************
*+Only+allow+numbers+and+one+decimal+in+text+boxes
***************************************************/
$('body').on('keydown+keyup+keypress+change+blur+focus+paste',+'input[type="text"]',+function(){
++++var+target+=+$(this);

++++var+prev_val+=+target.val();

++++setTimeout(function(){
++++++++var+chars+=+target.val().split("");

++++++++var+decimal_exist+=+false;
++++++++var+remove_char+=+false;

++++++++$.each(chars,+function(key,+value){
++++++++++++switch(value){
++++++++++++++++case+'0':
++++++++++++++++case+'1':
++++++++++++++++case+'2':
++++++++++++++++case+'3':
++++++++++++++++case+'4':
++++++++++++++++case+'5':
++++++++++++++++case+'6':
++++++++++++++++case+'7':
++++++++++++++++case+'8':
++++++++++++++++case+'9':
++++++++++++++++case+'.':
++++++++++++++++++++if(value+===+'.'){
++++++++++++++++++++++++if(decimal_exist+===+false){
++++++++++++++++++++++++++++decimal_exist+=+true;
++++++++++++++++++++++++}
++++++++++++++++++++++++else{
++++++++++++++++++++++++++++remove_char+=+true;
++++++++++++++++++++++++++++chars[''%2Bkey%2B'']+=+'';
++++++++++++++++++++++++}
++++++++++++++++++++}
++++++++++++++++++++break;
++++++++++++++++default:
++++++++++++++++++++remove_char+=+true;
++++++++++++++++++++chars[''%2Bkey%2B'']+=+'';
++++++++++++++++++++break;
++++++++++++}
++++++++});

++++++++if(prev_val+!=+target.val()+&&+remove_char+===+true){
++++++++++++target.val(chars.join(''))
++++++++}
++++},+0);
});|code-block|syntax|javascript|1039264|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>For anyone stumbling here like I did, here is a jQuery 1.10.2 version I wrote which is working very well for me albeit resource intensive:</p>

<pre><code>/***************************************************
* Only allow numbers and one decimal in text boxes
***************************************************/
$('body').on('keydown keyup keypress change blur focus paste', 'input[type="text"]', function(){
    var target = $(this);

    var prev_val = target.val();

    setTimeout(function(){
        var chars = target.val().split("");

        var decimal_exist = false;
        var remove_char = false;

        $.each(chars, function(key, value){
            switch(value){
                case '0':
                case '1':
                case '2':
                case '3':
                case '4':
                case '5':
                case '6':
                case '7':
                case '8':
                case '9':
                case '.':
                    if(value === '.'){
                        if(decimal_exist === false){
                            decimal_exist = true;
                        }
                        else{
                            remove_char = true;
                            chars[''+key+''] = '';
                        }
                    }
                    break;
                default:
                    remove_char = true;
                    chars[''+key+''] = '';
                    break;
            }
        });

        if(prev_val != target.val() &amp;&amp; remove_char === true){
            target.val(chars.join(''))
        }
    }, 0);
});
</code></pre>


blocks|key|1254258|text|对@rebisco的精彩答案进行了小小的更正，以完美地验证小数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1254259|function+isNumberKey(evt)+{
++++debugger;
++++var+charCode+=+(evt.which)+?+evt.which+:+event.keyCode;
++++if+(charCode+==+46+&&+evt.srcElement.value.split('.').length>1)+{
++++++++return+false;
++++}
++++if+(charCode+!=+46+&&+charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))
++++++++return+false;
++++return+true;
}|code-block|syntax|javascript|1254260|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>A small correction to @rebisco's brilliant answer to validate the decimal perfectly.</p>

<pre><code>function isNumberKey(evt) {
    debugger;
    var charCode = (evt.which) ? evt.which : event.keyCode;
    if (charCode == 46 &amp;&amp; evt.srcElement.value.split('.').length&gt;1) {
        return false;
    }
    if (charCode != 46 &amp;&amp; charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
        return false;
    return true;
}
</code></pre>


blocks|key|1255136|text|如果您希望它用于浮点值，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1255137|下面是我正在使用的函数|1255138|​|1255139|<HTML>

<HEAD>
++<SCRIPT+language=Javascript>
++++
++</SCRIPT>
</HEAD>

<BODY>
++<INPUT+id="txtChar"+onkeypress="return+check(event,value)"+type="text"+name="txtChar">
</BODY>

</HTML>|code-block|syntax|javascript|1255140|1255141|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|P|8|@]|9|@]|A|$]]|$1|F|3|G|5|H|7|Q|8|@]|9|@]|A|$I|J]]|$1|K|3|E|5|6|7|R|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|M|$]]

<p>If you want it for float values, </p>

<p>Here is the function I am using</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;HTML&gt;

&lt;HEAD&gt;
  &lt;SCRIPT language=Javascript&gt;
    &lt;!--
    function check(e, value) {
      //Check Charater
      var unicode = e.charCode ? e.charCode : e.keyCode;
      if (value.indexOf(".") != -1)
        if (unicode == 46) return false;
      if (unicode != 8)
        if ((unicode &lt; 48 || unicode &gt; 57) &amp;&amp; unicode != 46) return false;
    }
    //--&gt;
  &lt;/SCRIPT&gt;
&lt;/HEAD&gt;

&lt;BODY&gt;
  &lt;INPUT id="txtChar" onkeypress="return check(event,value)" type="text" name="txtChar"&gt;
&lt;/BODY&gt;

&lt;/HTML&gt;</code></pre>
</div>
</div>
</p>


blocks|key|1255257|text|++function+onlyDotsAndNumbers(txt,+event)+{
++++++++var+charCode+=+(event.which)+?+event.which+:+event.keyCode
++++++++if+(charCode+==+46)+{
++++++++++++if+(txt.value.indexOf(".")+<+0)
++++++++++++++++return+true;
++++++++++++else
++++++++++++++++return+false;
++++++++}

++++++++if+(txt.value.indexOf(".")+>+0)+{
++++++++++++var+txtlen+=+txt.value.length;
++++++++++++var+dotpos+=+txt.value.indexOf(".");
++++++++++++//Change+the+number+here+to+allow+more+decimal+points+than+2
++++++++++++if+((txtlen+-+dotpos)+>+2)
++++++++++++++++return+false;
++++++++}

++++++++if+(charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))
++++++++++++return+false;

++++++++return+true;
++++}


<input+type="text"+id="txtAmount"+onkeypress="return+onlyDotsAndNumbers(this,event);"+maxlength="10"+oncopy="return+false"+ondrag="return+false"+ondrop="return+false"+onpaste="return+false"+/>|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1255258|只有数字，一个小数点，没有复制粘贴。|unstyled|1255259|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>  function onlyDotsAndNumbers(txt, event) {
        var charCode = (event.which) ? event.which : event.keyCode
        if (charCode == 46) {
            if (txt.value.indexOf(&quot;.&quot;) &lt; 0)
                return true;
            else
                return false;
        }

        if (txt.value.indexOf(&quot;.&quot;) &gt; 0) {
            var txtlen = txt.value.length;
            var dotpos = txt.value.indexOf(&quot;.&quot;);
            //Change the number here to allow more decimal points than 2
            if ((txtlen - dotpos) &gt; 2)
                return false;
        }

        if (charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
            return false;

        return true;
    }


&lt;input type=&quot;text&quot; id=&quot;txtAmount&quot; onkeypress=&quot;return onlyDotsAndNumbers(this,event);&quot; maxlength=&quot;10&quot; oncopy=&quot;return false&quot; ondrag=&quot;return false&quot; ondrop=&quot;return false&quot; onpaste=&quot;return false&quot; /&gt;
</code></pre>
<p>Only Numbers, One decimal point, No Copy Paste.</p>


blocks|key|1253936|text|inputelement.onchange=+inputelement.onkeyup=+function+isnumber(e){
++++e=+window.event?+e.srcElement:+e.target;
++++while(e.value+&&+parseFloat(e.value)%2B''!=+e.value){
++++++++++++e.value=+e.value.slice(0,+-1);
++++}
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1253937|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>inputelement.onchange= inputelement.onkeyup= function isnumber(e){
    e= window.event? e.srcElement: e.target;
    while(e.value &amp;&amp; parseFloat(e.value)+''!= e.value){
            e.value= e.value.slice(0, -1);
    }
}
</code></pre>


blocks|key|1253976|text|function+integerwithdot(s,+iid){
++++++++var+i;
++++++++s+=+s.toString();
++++++++for+(i+=+0;+i+<+s.length;+i%2B%2B){
++++++++++++var+c;
++++++++++++if+(s.charAt(i)+==+".")+{
++++++++++++}+else+{
++++++++++++++++c+=+s.charAt(i);
++++++++++++}
++++++++++++if+(isNaN(c))+{
++++++++++++++++c+=+"";
++++++++++++++++for(i=0;i<s.length-1;i%2B%2B){
++++++++++++++++++++c+%2B=+s.charAt(i);
++++++++++++++++}
++++++++++++++++document.getElementById(iid).value+=+c;
++++++++++++++++return+false;
++++++++++++}
++++++++}
++++++++return+true;
++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1253977|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>function integerwithdot(s, iid){
        var i;
        s = s.toString();
        for (i = 0; i &lt; s.length; i++){
            var c;
            if (s.charAt(i) == ".") {
            } else {
                c = s.charAt(i);
            }
            if (isNaN(c)) {
                c = "";
                for(i=0;i&lt;s.length-1;i++){
                    c += s.charAt(i);
                }
                document.getElementById(iid).value = c;
                return false;
            }
        }
        return true;
    }
</code></pre>


blocks|key|1254041|text|假设您的文本框字段名为Income|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1254042|当您需要验证字段时，调用此验证方法：|1254043|function+validate()+{
++++var+currency+=+document.getElementById("Income").value;
++++++var+pattern+=+/%5E[1-9]\d*(?:\.\d{0,2})?$/+;
++++if+(pattern.test(currency))+{
++++++++alert("Currency+is+in+valid+format");
++++++++return+true;
++++}+
++++++++alert("Currency+is+not+in+valid+format!Enter+in+00.00+format");
++++++++return+false;
}|code-block|syntax|javascript|1254044|entityMap^0|B|6|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

<p>Suppose your textbox field name is <code>Income</code><br>
Call this validate method when you need to validate your field:</p>

<pre><code>function validate() {
    var currency = document.getElementById("Income").value;
      var pattern = /^[1-9]\d*(?:\.\d{0,2})?$/ ;
    if (pattern.test(currency)) {
        alert("Currency is in valid format");
        return true;
    } 
        alert("Currency is not in valid format!Enter in 00.00 format");
        return false;
}
</code></pre>


blocks|key|1039476|text|扩展@rebisco的答案。下面的代码将只允许在文本框中使用数字和单个‘.’(句点)。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039477|function+isNumberKey(evt)+{
++++++++var+charCode+=+(evt.which)+?+evt.which+:+event.keyCode;
++++++++if+(charCode+!=+46+&&+charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))+{
++++++++++++return+false;
++++++++}+else+{
++++++++++++//+If+the+number+field+already+has+.+then+don't+allow+to+enter+.+again.
++++++++++++if+(evt.target.value.search(/\./)+>+-1+&&+charCode+==+46)+{
++++++++++++++++return+false;
++++++++++++}
++++++++++++return+true;
++++++++}
++++}|code-block|syntax|javascript|1039478|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>Extending the @rebisco's answer. this below code will allow only numbers and single '.'(period) in the text box.</p>

<pre><code>function isNumberKey(evt) {
        var charCode = (evt.which) ? evt.which : event.keyCode;
        if (charCode != 46 &amp;&amp; charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57)) {
            return false;
        } else {
            // If the number field already has . then don't allow to enter . again.
            if (evt.target.value.search(/\./) &gt; -1 &amp;&amp; charCode == 46) {
                return false;
            }
            return true;
        }
    }
</code></pre>


blocks|key|1254527|text|更好的解决方案|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1254528|var+checkfloats+=+function(event){
++++var+charCode+=+(event.which)+?+event.which+:+event.keyCode;
++++if+(charCode+!=+46+&&+charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))
++++++++return+false;

++++if(event.target.value.indexOf('.')+>=0+&&+charCode+==+46)
++++++++return+false;

++++return+true;
}|code-block|syntax|javascript|1254529|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>Better solution</p>

<pre><code>var checkfloats = function(event){
    var charCode = (event.which) ? event.which : event.keyCode;
    if (charCode != 46 &amp;&amp; charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
        return false;

    if(event.target.value.indexOf('.') &gt;=0 &amp;&amp; charCode == 46)
        return false;

    return true;
}
</code></pre>


blocks|key|1254868|text|将输入限制到文本框以使其仅接受数字和小数点的另一种方法是在html输入中使用javascript。这对我来说很有效：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1254869|<input+type="text"+class="form-control"+id="price"+name="price"+placeholder="Price"+
vrequired+onkeyup="this.value=this.value.replace(/[%5E0-9.]/g,+'').replace(/(\..*)\./g,+'$1')">|code-block|syntax|javascript|1254870|-接受--|1254871|9|1254872|9.99|1254873|--不接受--|1254874|9.99.99|1254875|ABC|1254876|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|Y|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|Z|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|11|8|@]|9|@]|A|$]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

<p>alternative way to restrict input to a text-box so that it accepts only numbers and the decimal point is to 
use javascript inside the html input. This works for me:</p>

<pre><code>&lt;input type="text" class="form-control" id="price" name="price" placeholder="Price" 
vrequired onkeyup="this.value=this.value.replace(/[^0-9.]/g, '').replace(/(\..*)\./g, '$1')"&gt;
</code></pre>

<p>--Accepts--</p>

<p>9</p>

<p>9.99</p>

<p>--Do not accept--</p>

<p>9.99.99</p>

<p>ABC</p>


blocks|key|1040327|text|我选择在oninput事件上解决这个问题，以便处理键盘粘贴、鼠标粘贴和击键的问题。传递true或false以指示小数或整数验证。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1040328|它基本上是三个一行代码中的三个步骤。如果您不想截断小数，请注释第三步。在第三步中也可以对舍入进行调整。|1040329|//+Example+Decimal+usage;
//+<input+type="text"++oninput="ValidateNumber(this,+true);"+/>
//+Example+Integer+usage:
//+<input+type="text"++oninput="ValidateNumber(this,+false);"+/>
function+ValidateNumber(elm,+isDecimal)+{
++++try+{

++++++++//+For+integers,+replace+everything+except+for+numbers+with+blanks.
++++++++if+(!isDecimal)+
++++++++++++elm.value+=+elm.value.replace(/[%5E0-9]/g,+'');+
++++++++else+{
++++++++++++//+1.+For+decimals,+replace+everything+except+for+numbers+and+periods+with+blanks.
++++++++++++//+2.+Then+we'll+remove+all+leading+ocurrences+(duplicate)+periods
++++++++++++//+3.+Then+we'll+chop+off+anything+after+two+decimal+places.

++++++++++++//+1.+replace+everything+except+for+numbers+and+periods+with+blanks.
++++++++++++elm.value+=+elm.value.replace(/[%5E0-9.]/g,+'');

++++++++++++//2.+remove+all+leading+ocurrences+(duplicate)+periods
++++++++++++elm.value+=+elm.value.replace(/\.(?=.*\.)/g,+'');

++++++++++++//+3.+chop+off+anything+after+two+decimal+places.
++++++++++++//+In+comparison+to+lengh,+our+index+is+behind+one+count,+then+we+add+two+for+our+decimal+places.
++++++++++++var+decimalIndex+=+elm.value.indexOf('.');
++++++++++++if+(decimalIndex+!=+-1)+{+elm.value+=+elm.value.substr(0,+decimalIndex+%2B+3);+}
++++++++}
++++}
++++catch+(err)+{
++++++++alert("ValidateNumber+"+%2B+err);
++++}
}|code-block|syntax|javascript|1040330|entityMap^0|4|7|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

<p>I chose to tackle this on the <code>oninput</code> event in order to handle the issue for keyboard pasting, mouse pasting and key strokes. Pass true or false to indicate decimal or integer validation.</p>

<p>It's basically three steps in three one liners. If you don't want to truncate the decimals comment the third step. Adjustments for rounding can be made in the third step as well.</p>

<pre><code>// Example Decimal usage;
// &lt;input type="text"  oninput="ValidateNumber(this, true);" /&gt;
// Example Integer usage:
// &lt;input type="text"  oninput="ValidateNumber(this, false);" /&gt;
function ValidateNumber(elm, isDecimal) {
    try {

        // For integers, replace everything except for numbers with blanks.
        if (!isDecimal) 
            elm.value = elm.value.replace(/[^0-9]/g, ''); 
        else {
            // 1. For decimals, replace everything except for numbers and periods with blanks.
            // 2. Then we'll remove all leading ocurrences (duplicate) periods
            // 3. Then we'll chop off anything after two decimal places.

            // 1. replace everything except for numbers and periods with blanks.
            elm.value = elm.value.replace(/[^0-9.]/g, '');

            //2. remove all leading ocurrences (duplicate) periods
            elm.value = elm.value.replace(/\.(?=.*\.)/g, '');

            // 3. chop off anything after two decimal places.
            // In comparison to lengh, our index is behind one count, then we add two for our decimal places.
            var decimalIndex = elm.value.indexOf('.');
            if (decimalIndex != -1) { elm.value = elm.value.substr(0, decimalIndex + 3); }
        }
    }
    catch (err) {
        alert("ValidateNumber " + err);
    }
}
</code></pre>


blocks|key|1254132|text|function+isNumberKey(evt)
{
++++var+charCode+=+(evt.which)+?+evt.which+:+evt.keyCode;

++++if(charCode==8+%7C%7C+charCode==13%7C%7C+charCode==99%7C%7C+charCode==118+%7C%7C+charCode==46)
++++{++++
++++++++return+true;++
++++}

++++if+(charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))
++++{+++
++++++++return+false;+
++++}
++++return+true;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1254133|它将只允许使用数字，并允许您输入“。表示小数。|unstyled|1254134|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>function isNumberKey(evt)
{
    var charCode = (evt.which) ? evt.which : evt.keyCode;

    if(charCode==8 || charCode==13|| charCode==99|| charCode==118 || charCode==46)
    {    
        return true;  
    }

    if (charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
    {   
        return false; 
    }
    return true;
}
</code></pre>

<p>It will allow only numeric and will let you put "." for decimal. </p>


blocks|key|1039410|text|从@rebisco答案开始：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039411|function+count_appearance(mainStr,+searchFor)+{
++++return+(mainStr.split(searchFor).length+-+1);
}
function+isNumberKey(evt)
{
++++$return+=+true;
++++var+charCode+=+(evt.which)+?+evt.which+:+event.keyCode;
++++if+(charCode+!=+46+&&+charCode+>+31
++++++++++++&&+(charCode+<+48+%7C%7C+charCode+>+57))
++++++++$return+=+false;
++++$val+=+$(evt.originalTarget).val();
++++if+(charCode+==+46)+{
++++++++if+(count_appearance($val,+'.')+>+0)+{
++++++++++++$return+=+false;
++++++++}
++++++++if+($val.length+==+0)+{
++++++++++++$return+=+false;
++++++++}
++++}
++++return+$return;
}|code-block|syntax|javascript|1039412|仅允许此格式:+123123123.121213|1039413|在这里演示demo|offset|length|1039414|entityMap|0|LINK|mutability|MUTABLE|url|http://jsfiddle.net/UUu3d/^0|0|0|0|5|4|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|X|8|@]|9|@$K|Y|L|Z|1|10]]|A|$]]|$1|M|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

<p>Starting from @rebisco answer :</p>

<pre><code>function count_appearance(mainStr, searchFor) {
    return (mainStr.split(searchFor).length - 1);
}
function isNumberKey(evt)
{
    $return = true;
    var charCode = (evt.which) ? evt.which : event.keyCode;
    if (charCode != 46 &amp;&amp; charCode &gt; 31
            &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
        $return = false;
    $val = $(evt.originalTarget).val();
    if (charCode == 46) {
        if (count_appearance($val, '.') &gt; 0) {
            $return = false;
        }
        if ($val.length == 0) {
            $return = false;
        }
    }
    return $return;
}
</code></pre>

<p>Allows only this format : 123123123[.121213]</p>

<p>Demo here <a href="http://jsfiddle.net/UUu3d/" rel="nofollow">demo</a></p>


blocks|key|1039486|text|希望它能为你工作。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039487|<input+type="text"+onkeypress="return+chkNumeric(event)"+/>

<script>
++++function+chkNumeric(evt)+{
++++++++evt+=+(evt)+?+evt+:+window.event;
++++++++var+charCode+=+(evt.which)+?+evt.which+:+evt.keyCode;
++++++++if+(charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))+{
++++++++++++if+(charCode+==+46)+{+return+true;+}
++++++++++++else+{+return+false;+}
++++++++}
++++++++return+true;
++++}
</script>|code-block|syntax|javascript|1039488|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>Hope it will work for you.</p>

<pre><code>&lt;input type="text" onkeypress="return chkNumeric(event)" /&gt;

&lt;script&gt;
    function chkNumeric(evt) {
        evt = (evt) ? evt : window.event;
        var charCode = (evt.which) ? evt.which : evt.keyCode;
        if (charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57)) {
            if (charCode == 46) { return true; }
            else { return false; }
        }
        return true;
    }
&lt;/script&gt;
</code></pre>


blocks|key|1039717|text|下面的代码对我很有效|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039718|包含"onkeypress“事件的输入框如下|1039719|<input+type="text"+onkeypress="return+isNumberKey(this,event);"+/>|code-block|syntax|javascript|1039720|函数"isNumberKey“如下|1039721|​|1039722|function+isNumberKey(txt,+evt)+{
++var+charCode+=+(evt.which)+?+evt.which+:+evt.keyCode;
++if+(charCode+==+46)+{
++++//Check+if+the+text+already+contains+the+.+character
++++if+(txt.value.indexOf('.')+===+-1)+{
++++++++return+true;
++++}+else+{
++++++++return+false;
++++}
++}+else+{
++++if+(charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))
++++++++return+false;
++}
++return+true;
}|1039723|1039724|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|T|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|U|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|V|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|O|3|L|5|6|7|X|8|@]|9|@]|A|$]]|$1|P|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|Q|$]]

<p>Following code worked for me</p>

<p>The input box with "onkeypress" event as follows</p>

<pre><code>&lt;input type="text" onkeypress="return isNumberKey(this,event);" /&gt;
</code></pre>

<p>The function "isNumberKey" is as follows</p>

<p><div class="snippet" data-lang="js" data-hide="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>function isNumberKey(txt, evt) {
  var charCode = (evt.which) ? evt.which : evt.keyCode;
  if (charCode == 46) {
    //Check if the text already contains the . character
    if (txt.value.indexOf('.') === -1) {
        return true;
    } else {
        return false;
    }
  } else {
    if (charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
        return false;
  }
  return true;
}</code></pre>
</div>
</div>
</p>


blocks|key|1039760|text|我观察到，对于这里提供的所有答案，如果我们在textbox中选择文本的某一部分并尝试覆盖该部分，事情将不起作用。所以我修改了这个函数，如下：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039761|++++<HTML>
++<HEAD>
++++<SCRIPT+language=Javascript>
+++++++
++++</SCRIPT>
++</HEAD>
++<BODY>
++++<INPUT+id="txtChar"+onkeypress="return+isNumberKey(event)"+
+++++++++++type="text"+name="txtChar">
++</BODY>
</HTML>|code-block|syntax|javascript|1039762|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>I observed that for all the answers provided here, the things are not working if we select some portion of the text in textbox and try to overwrite that part.
So I modified the function which is as below:</p>

<pre><code>    &lt;HTML&gt;
  &lt;HEAD&gt;
    &lt;SCRIPT language=Javascript&gt;
       &lt;!--
       function isNumberKey(evt)
       {
         var charCode = (evt.which) ? evt.which : event.keyCode;

if (charCode != 46 &amp;&amp; charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
{
        return false;
}
 if (charCode == 46 &amp;&amp; evt.srcElement.value.split('.').length&gt;1 )
    {

        return false;

    } 

 if(evt.srcElement.selectionStart&lt;evt.srcElement.selectionEnd)
    {
          return true;
    }

  if(evt.srcElement.value.split('.').length&gt;1 &amp;&amp; evt.srcElement.value.split('.')[1].length==2)
  {

     return false;
  }


    return true;
       }


       //--&gt;
    &lt;/SCRIPT&gt;
  &lt;/HEAD&gt;
  &lt;BODY&gt;
    &lt;INPUT id="txtChar" onkeypress="return isNumberKey(event)" 
           type="text" name="txtChar"&gt;
  &lt;/BODY&gt;
&lt;/HTML&gt;
</code></pre>


blocks|key|1039826|text|对于十进制数字，也允许负数在小数点后有两位小数...我将函数修改为：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1039827|<input+type="text"+id="txtSample"+onkeypress="return+isNumberKey(event,this)"/>



function+isNumberKey(evt,+element){

++++++++var+charCode+=+(evt.which)+?+evt.which+:+event.keyCode
++++++++if+(charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57)+&&+!(charCode+==+46+%7C%7C+charCode+==+8+%7C%7C+charCode+==+45))
++++++++++++return+false;
++++++++else+{
++++++++++++var+len+=+$(element).val().length;

++++++++++++//+Validation+Point
++++++++++++var+index+=+$(element).val().indexOf('.');
++++++++++++if+((index+>+0+&&+charCode+==+46)+%7C%7C+len+==+0+&&+charCode+==+46)+{
++++++++++++++++return+false;
++++++++++++}
++++++++++++if+(index+>+0)+{
++++++++++++++++var+CharAfterdot+=+(len+%2B+1)+-+index;
++++++++++++++++if+(CharAfterdot+>+3)+{
++++++++++++++++++++return+false;
++++++++++++++++}
++++++++++++}

++++++++++++//+Validating+Negative+sign
++++++++++++index+=+$(element).val().indexOf('-');
++++++++++++if+((index+>+0+&&+charCode+==+45)+%7C%7C+(len+>+0+&&+charCode+==+45))+{
++++++++++++++++return+false;
++++++++++++}
++++++++}
++++++++return+true;
++++}|code-block|syntax|javascript|1039828|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

<p>For Decimal numbers and also allowing Negatives numbers with 2 places for decimals after the point... I modified the function to:</p>

<pre><code>&lt;input type="text" id="txtSample" onkeypress="return isNumberKey(event,this)"/&gt;



function isNumberKey(evt, element){

        var charCode = (evt.which) ? evt.which : event.keyCode
        if (charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57) &amp;&amp; !(charCode == 46 || charCode == 8 || charCode == 45))
            return false;
        else {
            var len = $(element).val().length;

            // Validation Point
            var index = $(element).val().indexOf('.');
            if ((index &gt; 0 &amp;&amp; charCode == 46) || len == 0 &amp;&amp; charCode == 46) {
                return false;
            }
            if (index &gt; 0) {
                var CharAfterdot = (len + 1) - index;
                if (CharAfterdot &gt; 3) {
                    return false;
                }
            }

            // Validating Negative sign
            index = $(element).val().indexOf('-');
            if ((index &gt; 0 &amp;&amp; charCode == 45) || (len &gt; 0 &amp;&amp; charCode == 45)) {
                return false;
            }
        }
        return true;
    }
</code></pre>


blocks|key|1254783|text|<input+type="text"+class="number_only"+/>++++
<script>
$(document).ready(function()+{
++++$('.number_only').keypress(function+(event)+{
++++++++return+isNumber(event,+this)
++++});++++++++
});

function+isNumber(evt,+element)+{
++++var+charCode+=+(evt.which)+?+evt.which+:+event.keyCode

++++if+((charCode+!=+45+%7C%7C+$(element).val().indexOf('-')+!=+-1)+&&+(charCode+!=+46+%7C%7C+$(element).val().indexOf('.')+!=+-1)+&&+((charCode+<+48+&&+charCode+!=+8)+%7C%7C+charCode+>+57)){
++++++++return+false;
++++}
++++else+{
++++++++return+true;
++++}
}+
</script>|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1254784|http://www.encodedna.com/2013/05/enter-only-numbers-using-jquery.htm|unstyled|offset|length|1254785|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|1W|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|Q|8|@]|9|@$G|R|H|S|1|T]]|A|$]]|$1|I|3|-4|5|F|7|U|8|@]|9|@]|A|$]]]|J|$K|$5|L|M|N|A|$O|E]]]]

<pre><code>&lt;input type="text" class="number_only" /&gt;    
&lt;script&gt;
$(document).ready(function() {
    $('.number_only').keypress(function (event) {
        return isNumber(event, this)
    });        
});

function isNumber(evt, element) {
    var charCode = (evt.which) ? evt.which : event.keyCode

    if ((charCode != 45 || $(element).val().indexOf('-') != -1) &amp;&amp; (charCode != 46 || $(element).val().indexOf('.') != -1) &amp;&amp; ((charCode &lt; 48 &amp;&amp; charCode != 8) || charCode &gt; 57)){
        return false;
    }
    else {
        return true;
    }
} 
&lt;/script&gt;
</code></pre>

<p><a href="http://www.encodedna.com/2013/05/enter-only-numbers-using-jquery.htm" rel="nofollow">http://www.encodedna.com/2013/05/enter-only-numbers-using-jquery.htm</a></p>


blocks|key|1254933|text|使用纯Javascript示例现场演示的最佳和有效的解决方案：https://jsfiddle.net/manoj2010/ygkpa89o/|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1254934|<script>
function+removeCommas(nStr)+{
++++if+(nStr+==+null+%7C%7C+nStr+==+"")
++++++++return+"";+
++++return+nStr.toString().replace(/,/g,+"");
}

function+NumbersOnly(myfield,+e,+dec,neg)
{++++++++
++++if+(isNaN(removeCommas(myfield.value))+&&+myfield.value+!=+"-")+{
++++++++return+false;
++++}
++++var+allowNegativeNumber+=+neg+%7C%7C+false;
++++var+key;
++++var+keychar;

++++if+(window.event)
++++++++key+=+window.event.keyCode;
++++else+if+(e)
++++++++key+=+e.which;
++++else
++++++++return+true;
++++keychar+=+String.fromCharCode(key);
++++var+srcEl+=+e.srcElement+?+e.srcElement+:+e.target;++++
++++//+control+keys
++++if+((key+==+null)+%7C%7C+(key+==+0)+%7C%7C+(key+==+8)+%7C%7C
++++++++++++++++(key+==+9)+%7C%7C+(key+==+13)+%7C%7C+(key+==+27))
++++++++return+true;

++++//+numbers
++++else+if+((("0123456789").indexOf(keychar)+>+-1))
++++++++return+true;

++++//+decimal+point+jump
++++else+if+(dec+&&+(keychar+==+"."))+{
++++++++//myfield.form.elements[dec].focus();
++++++++return+srcEl.value.indexOf(".")+==+-1;++++++++
++++}

++++//allow+negative+numbers
++++else+if+(allowNegativeNumber+&&+(keychar+==+"-"))+{++++
++++++++return+(srcEl.value.length+==+0+%7C%7C+srcEl.value+==+"0.00")
++++}
++++else
++++++++return+false;
}
</script>
<input+name="txtDiscountSum"+type="text"+onKeyPress="return+NumbersOnly(this,+event,true)"+/>+|code-block|syntax|javascript|1254935|​|1254936|entityMap|0|LINK|mutability|MUTABLE|url|https://jsfiddle.net/manoj2010/ygkpa89o/^0|V|14|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|C|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

<p>Best and working solution with Pure-Javascript sample
Live demo : <a href="https://jsfiddle.net/manoj2010/ygkpa89o/" rel="nofollow noreferrer">https://jsfiddle.net/manoj2010/ygkpa89o/</a>
<div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script&gt;
function removeCommas(nStr) {
    if (nStr == null || nStr == "")
        return ""; 
    return nStr.toString().replace(/,/g, "");
}

function NumbersOnly(myfield, e, dec,neg)
{        
    if (isNaN(removeCommas(myfield.value)) &amp;&amp; myfield.value != "-") {
        return false;
    }
    var allowNegativeNumber = neg || false;
    var key;
    var keychar;

    if (window.event)
        key = window.event.keyCode;
    else if (e)
        key = e.which;
    else
        return true;
    keychar = String.fromCharCode(key);
    var srcEl = e.srcElement ? e.srcElement : e.target;    
    // control keys
    if ((key == null) || (key == 0) || (key == 8) ||
                (key == 9) || (key == 13) || (key == 27))
        return true;

    // numbers
    else if ((("0123456789").indexOf(keychar) &gt; -1))
        return true;

    // decimal point jump
    else if (dec &amp;&amp; (keychar == ".")) {
        //myfield.form.elements[dec].focus();
        return srcEl.value.indexOf(".") == -1;        
    }

    //allow negative numbers
    else if (allowNegativeNumber &amp;&amp; (keychar == "-")) {    
        return (srcEl.value.length == 0 || srcEl.value == "0.00")
    }
    else
        return false;
}
&lt;/script&gt;
&lt;input name="txtDiscountSum" type="text" onKeyPress="return NumbersOnly(this, event,true)" /&gt; </code></pre>
</div>
</div>
</p>


blocks|key|1255013|text|我自己在解决这个问题，这就是我到目前为止所得到的。这或多或少是有效的，但由于新值检查，之后不可能添加减号。也不允许逗号作为一千个分隔符，只能作为小数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1255014|它不是完美的，但可能会给出一些想法。|1255015|app.directive('isNumber',+function+()+{
++++++++++++return+function+(scope,+elem,+attrs)+{
++++++++++++++++elem.bind('keypress',+function+(evt)+{
++++++++++++++++++++var+keyCode+=+(evt.which)+?+evt.which+:+event.keyCode;
++++++++++++++++++++var+testValue+=+(elem[0].value+%2B+String.fromCharCode(keyCode)+%2B+"0").replace(/+/g,+"");+//check+ignores+spaces
++++++++++++++++++++var+regex+=+/%5E\-?\d%2B((\.%7C\,)\d%2B)?$/;++++++++++++++++++++++++
++++++++++++++++++++var+allowedChars+=+[8,9,13,27,32,37,39,44,45,+46]+//control+keys+and+separators+++++++++++++

+++++++++++++++++++//allows+numbers,+separators+and+controll+keys+and+rejects+others
++++++++++++++++++++if+((keyCode+>+47+&&+keyCode+<+58)+%7C%7C+allowedChars.indexOf(keyCode)+>=+0)+{+++++++++++++
++++++++++++++++++++++++//test+the+string+with+regex,+decline+if+doesn't+fit
++++++++++++++++++++++++if+(elem[0].value+!=+""+&&+!regex.test(testValue))+{
++++++++++++++++++++++++++++event.preventDefault();
++++++++++++++++++++++++++++return+false;
++++++++++++++++++++++++}
++++++++++++++++++++++++return+true;
++++++++++++++++++++}
++++++++++++++++++++event.preventDefault();
++++++++++++++++++++return+false;
++++++++++++++++});
++++++++++++};
++++++++});|code-block|syntax|javascript|1255016|允许：|1255017|11+11+.245+(控制器模糊时格式设置为1111.245)|1255018|11,44|1255019|-123.123|1255020|-1+014|1255021|0123+(模糊格式化为123)|1255022|不允许：|1255023|!@#$/*|1255024|abc|1255025|11.11.1|1255026|11,11.1|1255027|.42|1255028|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|19|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|1A|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|1B|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|1C|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|1D|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1E|8|@]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1F|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|1G|8|@]|9|@]|A|$]]|$1|U|3|V|5|6|7|1H|8|@]|9|@]|A|$]]|$1|W|3|X|5|6|7|1I|8|@]|9|@]|A|$]]|$1|Y|3|Z|5|6|7|1J|8|@]|9|@]|A|$]]|$1|10|3|11|5|6|7|1K|8|@]|9|@]|A|$]]|$1|12|3|13|5|6|7|1L|8|@]|9|@]|A|$]]|$1|14|3|15|5|6|7|1M|8|@]|9|@]|A|$]]|$1|16|3|-4|5|6|7|1N|8|@]|9|@]|A|$]]]|17|$]]

<p>Working on the issue myself, and that's what I've got so far. This more or less works, but it's impossible to add minus afterwards due to the new value check. Also doesn't allow comma as a thousand separator, only decimal.</p>

<p>It's not perfect, but might give some ideas. </p>

<pre><code>app.directive('isNumber', function () {
            return function (scope, elem, attrs) {
                elem.bind('keypress', function (evt) {
                    var keyCode = (evt.which) ? evt.which : event.keyCode;
                    var testValue = (elem[0].value + String.fromCharCode(keyCode) + "0").replace(/ /g, ""); //check ignores spaces
                    var regex = /^\-?\d+((\.|\,)\d+)?$/;                        
                    var allowedChars = [8,9,13,27,32,37,39,44,45, 46] //control keys and separators             

                   //allows numbers, separators and controll keys and rejects others
                    if ((keyCode &gt; 47 &amp;&amp; keyCode &lt; 58) || allowedChars.indexOf(keyCode) &gt;= 0) {             
                        //test the string with regex, decline if doesn't fit
                        if (elem[0].value != "" &amp;&amp; !regex.test(testValue)) {
                            event.preventDefault();
                            return false;
                        }
                        return true;
                    }
                    event.preventDefault();
                    return false;
                });
            };
        });
</code></pre>

<p>Allows: </p>

<p>11 11 .245 (in controller formatted on blur to 1111.245)</p>

<p>11,44 </p>

<p>-123.123</p>

<p>-1 014</p>

<p>0123 (formatted on blur to 123)</p>

<p>doesn't allow: </p>

<p>!@#$/*</p>

<p>abc</p>

<p>11.11.1</p>

<p>11,11.1</p>

<p>.42</p>


blocks|key|1040210|text|<input+type="text"+onkeypress="return+isNumberKey(event,this)">

<script>
+++function+isNumberKey(evt,+obj)+{

++++++++++++var+charCode+=+(evt.which)+?+evt.which+:+event.keyCode
++++++++++++var+value+=+obj.value;
++++++++++++var+dotcontains+=+value.indexOf(".")+!=+-1;
++++++++++++if+(dotcontains)
++++++++++++++++if+(charCode+==+46)+return+false;
++++++++++++if+(charCode+==+46)+return+true;
++++++++++++if+(charCode+>+31+&&+(charCode+<+48+%7C%7C+charCode+>+57))
++++++++++++++++return+false;
++++++++++++return+true;
++++++++}


</script>|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1040211|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>&lt;input type="text" onkeypress="return isNumberKey(event,this)"&gt;

&lt;script&gt;
   function isNumberKey(evt, obj) {

            var charCode = (evt.which) ? evt.which : event.keyCode
            var value = obj.value;
            var dotcontains = value.indexOf(".") != -1;
            if (dotcontains)
                if (charCode == 46) return false;
            if (charCode == 46) return true;
            if (charCode &gt; 31 &amp;&amp; (charCode &lt; 48 || charCode &gt; 57))
                return false;
            return true;
        }


&lt;/script&gt;
</code></pre>


blocks|key|1040017|text|document.getElementById('value').addEventListener('keydown',+function(e)+{
++++var+key+++=+e.keyCode+?+e.keyCode+:+e.which;

/*lenght+of+value+to+use+with+index+to+know+how+many+numbers+after.*/

++++var+len+=+$('#value').val().length;
++++var+index+=+$('#value').val().indexOf('.');
++++if+(!(+[8,+9,+13,+27,+46,+110,+190].indexOf(key)+!==+-1+%7C%7C
++++++++++++++++++++(key+==+65+&&+(+e.ctrlKey+%7C%7C+e.metaKey++)+)+%7C%7C
++++++++++++++++++++(key+>=+35+&&+key+<=+40)+%7C%7C
++++++++++++++++++++(key+>=+48+&&+key+<=+57+&&+!(e.shiftKey+%7C%7C+e.altKey))+%7C%7C
++++++++++++++++++++(key+>=+96+&&+key+<=+105)
++++++++++++)){
++++++++e.preventDefault();
++++}

/*if+theres+a+.+count+how+many+and+if+reachs+2+digits+after+.+it+blocks*/+

++++if+(index+>+0)+{
++++++++var+CharAfterdot+=+(len+%2B+1)+-+index;
++++++++if+(CharAfterdot+>+3)+{

/*permits+the+backsapce+to+remove+:D+could+be+improved*/

++++++++++++if+(!(key+==+8))
++++++++++++{
++++++++++++++++e.preventDefault();
++++++++++++}

/*blocks+if+you+try+to+add+a+new+.+*/

++++++++}else+if+(+key+==+110)+{
++++++++++++e.preventDefault();
++++++++}

/*if+you+try+to+add+a+.+and+theres+no+digit+yet+it+adds+a+0.*/

++++}+else+if(+key+==+110&&+len==0){
++++++++e.preventDefault();
++++++++$('#value').val('0.');
++++}
});|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1040018|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>document.getElementById('value').addEventListener('keydown', function(e) {
    var key   = e.keyCode ? e.keyCode : e.which;

/*lenght of value to use with index to know how many numbers after.*/

    var len = $('#value').val().length;
    var index = $('#value').val().indexOf('.');
    if (!( [8, 9, 13, 27, 46, 110, 190].indexOf(key) !== -1 ||
                    (key == 65 &amp;&amp; ( e.ctrlKey || e.metaKey  ) ) ||
                    (key &gt;= 35 &amp;&amp; key &lt;= 40) ||
                    (key &gt;= 48 &amp;&amp; key &lt;= 57 &amp;&amp; !(e.shiftKey || e.altKey)) ||
                    (key &gt;= 96 &amp;&amp; key &lt;= 105)
            )){
        e.preventDefault();
    }

/*if theres a . count how many and if reachs 2 digits after . it blocks*/ 

    if (index &gt; 0) {
        var CharAfterdot = (len + 1) - index;
        if (CharAfterdot &gt; 3) {

/*permits the backsapce to remove :D could be improved*/

            if (!(key == 8))
            {
                e.preventDefault();
            }

/*blocks if you try to add a new . */

        }else if ( key == 110) {
            e.preventDefault();
        }

/*if you try to add a . and theres no digit yet it adds a 0.*/

    } else if( key == 110&amp;&amp; len==0){
        e.preventDefault();
        $('#value').val('0.');
    }
});
</code></pre>


<p>How can I restrict input to a text-box so that it accepts only numbers and the decimal point?</p>


Restricting input to textbox: allowing only numbers and decimal point

jQuery

如何将输入限制在文本框中，使其只接受数字和小数点？

问将输入限制为文本框:仅允许数字和小数点
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