blocks|key|1477831|text|我建议使用正则表达式：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1477832|var+intRegex+=+/%5E\d%2B$/;
var+floatRegex+=+/%5E((\d%2B(\.\d+*)?)%7C((\d*\.)?\d%2B))$/;

var+str+=+$('#myTextBox').val();
if(intRegex.test(str)+%7C%7C+floatRegex.test(str))+{
+++alert('I+am+a+number');
+++...
}|code-block|syntax|javascript|1477833|或者按照@Platinum的建议使用单个正则表达式：|1477834|var+numberRegex+=+/%5E[%2B-]?\d%2B(\.\d%2B)?([eE][%2B-]?\d%2B)?$/;
var+str+=+$('#myTextBox').val();
if(numberRegex.test(str))+{
+++alert('I+am+a+number');
+++...
}++++|1477835|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

I would suggest using regexes:

<pre><code>var intRegex = /^\d+$/;
var floatRegex = /^((\d+(\.\d *)?)|((\d*\.)?\d+))$/;

var str = $('#myTextBox').val();
if(intRegex.test(str) || floatRegex.test(str)) {
 alert('I am a number');
 ...
}
</code></pre>

Or with a single regex as per @Platinum Azure's suggestion:

<pre><code>var numberRegex = /^[+-]?\d+(\.\d+)?([eE][+-]?\d+)?$/;
var str = $('#myTextBox').val();
if(numberRegex.test(str)) {
 alert('I am a number');
 ...
} 
</code></pre>

blocks|key|1263373|text|忘记正则表达式吧。为此，JavaScript有一个内置函数：isNaN()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1263374|isNaN(123)+++++++++++//+false
isNaN(-1.23)+++++++++//+false
isNaN(5-2)+++++++++++//+false
isNaN(0)+++++++++++++//+false
isNaN("100")+++++++++//+false
isNaN("Hello")+++++++//+true
isNaN("2005/12/12")++//+true|code-block|syntax|javascript|1263375|就这么叫吧：|1263376|if+(isNaN(+$("#whatever").val()+))+{
++++//+It+isn't+a+number
}+else+{
++++//+It+is+a+number
}|1263377|entityMap^0|U|7|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

Forget regular expressions. JavaScript has a builtin function for this: <code>isNaN()</code>:

<pre><code>isNaN(123) // false
isNaN(-1.23) // false
isNaN(5-2) // false
isNaN(0) // false
isNaN("100") // false
isNaN("Hello") // true
isNaN("2005/12/12") // true
</code></pre>

Just call it like so:

<pre><code>if (isNaN( $("#whatever").val() )) {
 // It isn't a number
} else {
 // It is a number
}
</code></pre>

blocks|key|1478049|text|有一种更简单的方法来检查变量是否为整数。您可以使用$.isNumeric()函数。例如：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1478050|$.isNumeric(+10+);+++++//+true|code-block|syntax|javascript|1478051|这将返回true，但如果您将字符串放在10的位置，则将返回false。|1478052|我希望这对你有用。|1478053|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

there is a simpler way of checking if a variable is an integer. you can use $.isNumeric() function. e.g.

<pre><code>$.isNumeric( 10 ); // true
</code></pre>

this will return true but if you put a string in place of the 10, you will get false.

I hope this works for you.

blocks|key|1478089|text|可以使用下面的脚本检查value是否为有效的整数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1478090|++function+myFunction()+{
++++var+a+=+parseInt("10000000");
++++if+(!isNaN(a)+&&+a+<=+2147483647+&&+a+>=+-2147483647){
++++alert("is+integer");+
++++}+else+{
+++++alert("not+integer");+
++++}
}|code-block|syntax|javascript|1478091|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|$]]

Following script can be used to check whether value is valid integer or not.

<pre><code> function myFunction() {
 var a = parseInt("10000000");
 if (!isNaN(a) &amp;&amp; a &lt;= 2147483647 &amp;&amp; a &gt;= -2147483647){
 alert("is integer"); 
 } else {
 alert("not integer"); 
 }
}
</code></pre>

blocks|key|1477944|text|值验证不是jQuery的职责。为此，您可以使用纯JavaScript。我想到的两种方式是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1477945|/%5E\d%2B$/.match(value)
Number(value)+==+value|code-block|syntax|javascript|1477946|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|$]]

Value validation wouldn't be a responsibility of jQuery. You can use pure JavaScript for this. Two ways that come to my mind are:

<pre><code>/^\d+$/.match(value)
Number(value) == value
</code></pre>

blocks|key|1263500|text|String.prototype.isNumeric+=+function()+{
++++var+s+=+this.replace(',',+'.').replace(/\s%2B/g,+'');
return+s+==+0+%7C%7C+(s/s);
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1263501|用法|unstyled|1263502|'9.1'.isNumeric()+->+1
'0xabc'.isNumeric()+->+1
'10,1'.isNumeric()+->+1
'str'.isNumeric()+->+NaN|1263503|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre><code>String.prototype.isNumeric = function() {
 var s = this.replace(',', '.').replace(/\s+/g, '');
return s == 0 || (s/s);
}
</code></pre>

usage

<pre><code>'9.1'.isNumeric() -&gt; 1
'0xabc'.isNumeric() -&gt; 1
'10,1'.isNumeric() -&gt; 1
'str'.isNumeric() -&gt; NaN
</code></pre>

blocks|key|1263575|text|var+yourfield+=+$('fieldname').val();

if($.isNumeric(yourfield))+{+
++++++++console.log('IM+A+NUMBER');
}+else+{+
++++++++console.log('not+a+number');
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1263576|JQUERY+DOCS：|unstyled|1263577|https://api.jquery.com/jQuery.isNumeric/|offset|length|1263578|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|0|14|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|S|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|T|8|@]|9|@$I|U|J|V|1|W]]|A|$]]|$1|K|3|-4|5|F|7|X|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|H]]]]

<pre><code>var yourfield = $('fieldname').val();

if($.isNumeric(yourfield)) { 
 console.log('IM A NUMBER');
} else { 
 console.log('not a number');
}
</code></pre>

JQUERY DOCS:

<a href="https://api.jquery.com/jQuery.isNumeric/" rel="nofollow">https://api.jquery.com/jQuery.isNumeric/</a>

blocks|key|1263264|text|jQuery是一组JavaScript函数，对吗？因此，您可以使用JavaScript的正则表达式支持来验证字符串。如果您愿意，也可以将其放在jQuery回调中，因为这些回调只接受匿名声明的函数体，并且函数仍然是JavaScript。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1263265|链接：http://www.regular-expressions.info/javascript.html|offset|length|1263266|entityMap|0|LINK|mutability|MUTABLE|url|http://www.regular-expressions.info/javascript.html^0|0|3|1F|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

jQuery is a set of JavaScript functions, right? So you could use JavaScript's regular expression support to validate the string. You can put this in a jQuery callback if you like, too, since those just take anonymously-declared function bodies and the functions are still JavaScript.
Link: <a href="http://www.regular-expressions.info/javascript.html" rel="nofollow noreferrer">http://www.regular-expressions.info/javascript.html</a>

blocks|key|1263517|text|$(document).ready(function+()+{



++++$("#cust_zip").keypress(function+(e)+{
++++++++//var+z+=+document.createUserForm.cust_mobile1.value;
++++++++//alert(z);
++++++++if+(e.which+!=+8+&&+e.which+!=+0+&&+(e.which+<+48+%7C%7C+e.which+>+57))+{

++++++++++++$("#errmsgzip").html("Digits+Only.").show().fadeOut(3000);
++++++++++++return+false;
++++++++}
++++});
});|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1263518|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).ready(function () {



 $("#cust_zip").keypress(function (e) {
 //var z = document.createUserForm.cust_mobile1.value;
 //alert(z);
 if (e.which != 8 &amp;&amp; e.which != 0 &amp;&amp; (e.which &lt; 48 || e.which &gt; 57)) {

 $("#errmsgzip").html("Digits Only.").show().fadeOut(3000);
 return false;
 }
 });
});
</code></pre>

I have a simple <code>textbox</code> in which users enter number.
 Does jQuery have a <code>isDigit</code> function that will allow me to show an alert box if users enter something other than digits?

The field can have decimal points as well.

checking if number entered is a digit in jquery

jQuery

我有一个简单的textbox，用户在其中输入数字。jQuery是否有一个isDigit函数，允许我在用户输入数字以外的内容时显示一个警告框？该字段也可以有小数点。

问检查输入的数字是否为jquery中的数字
EN

回答 9

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问检查输入的数字是否为jquery中的数字EN

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问检查输入的数字是否为jquery中的数字
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