blocks|key|785748|text|使用以下代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|785749|​|785750|function+isOdd(num)+{+return+num+%25+2;}
console.log("1+is+"+%2B+isOdd(1));
console.log("2+is+"+%2B+isOdd(2));
console.log("3+is+"+%2B+isOdd(3));
console.log("4+is+"+%2B+isOdd(4));|code-block|syntax|javascript|785751|785752|1表示奇数，0表示偶数。|785753|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]]|$1|I|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|R|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|M|$]]

<p>Use the below code:</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>function isOdd(num) { return num % 2;}
console.log("1 is " + isOdd(1));
console.log("2 is " + isOdd(2));
console.log("3 is " + isOdd(3));
console.log("4 is " + isOdd(4));</code></pre>
</div>
</div>
</p>

<p>1 represents an odd number, while 0 represents an even number.</p>


blocks|key|999979|text|你可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|999980|function+isEven(value){
++++if+(value%252+==+0)
++++++++return+true;
++++else
++++++++return+false;
}|code-block|syntax|javascript|999981|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>You could do something like this:</p>

<pre><code>function isEven(value){
    if (value%2 == 0)
        return true;
    else
        return false;
}
</code></pre>


blocks|key|999993|text|function+isEven(x)+{+return+(x%252)==0;+}
function+isOdd(x)+{+return+!isEven(x);+}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|999994|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 isEven(x) { return (x%2)==0; }
function isOdd(x) { return !isEven(x); }
</code></pre>


blocks|key|785920|text|递归减去2，直到达到-1或0(显然只适用于正整数)+:)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|785921|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

<p>Subtract 2 to it recursively until you reach either -1 or 0 (only works for positive integers obviously) :)</p>


blocks|key|785956|text|if+(X+%25+2+===+0){
}+else+{
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|785957|将X替换为您的数字(可以来自变量)。If语句在数字为偶数时运行，Else语句在数字为奇数时运行。|unstyled|785958|如果您只想知道给定的数字是否为奇数：|785959|if+(X+%25+2+!==+0){
}|785960|同样，将X替换为数字或变量。|785961|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|P|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$B|C]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|F|7|T|8|@]|9|@]|A|$]]]|N|$]]

<pre><code>if (X % 2 === 0){
} else {
}
</code></pre>

<p>Replace X with your number (can come from a variable). The If statement runs when the number is even, the Else when it is odd.</p>

<p>If you just want to know if any given number is odd:</p>

<pre><code>if (X % 2 !== 0){
}
</code></pre>

<p>Again, replace X with a number or variable.</p>


blocks|key|785999|text|您可以使用for语句和条件来确定一个数字或一系列数字是否为奇数：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|786000|for+(var+i=1;+i<=5;+i%2B%2B)+
if+(i%252+!==+0)+{
++++console.log(i)
}|code-block|syntax|javascript|786001|这将打印1到5之间的每个奇数。|786002|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

<p>You can use a for statement and a conditional to determine if a number or series of numbers is odd:</p>

<pre><code>for (var i=1; i&lt;=5; i++) 
if (i%2 !== 0) {
    console.log(i)
}
</code></pre>

<p>This will print every odd number between 1 and 5.</p>


blocks|key|1000288|text|这可以通过一小段代码来解决：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1000289|function+isEven(value)+{
++++return+!(value+%25+2)
}|code-block|syntax|javascript|1000290|希望这能有所帮助:)|1000291|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

<p>This can be solved with a small snippet of code:</p>
<pre><code>function isEven(value) {
    return !(value % 2)
}
</code></pre>
<p>Hope this helps :)</p>


blocks|key|1000321|text|像许多语言一样，Javascript有一个modulus+operator+%25，它可以找到除法的剩余部分。如果除以2后没有余数，则一个数字是偶数：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1000322|//+this+expression+is+true+if+"number"+is+even,+false+otherwise
(number+%25+2+==+0)|code-block|syntax|javascript|1000323|对于甚至是整数的测试，这是一个非常常见的习惯用法。|1000324|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Arithmetic_Operators#.C2.A0.25_%2528Modulus%2529^0|12|1|L|I|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@$9|X|A|Y|1|Z]]|E|$]]|$1|F|3|G|5|H|7|10|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|11|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|12|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|T]]]]

<p>Like many languages, Javascript has a <a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Arithmetic_Operators#.C2.A0.25_%28Modulus%29" rel="noreferrer">modulus operator <code>%</code></a>, that finds the remainder of division. If there is no remainder after division by 2, a number is even:</p>

<pre><code>// this expression is true if "number" is even, false otherwise
(number % 2 == 0)
</code></pre>

<p>This is a very common idiom for testing for even integers.</p>


blocks|key|786169|text|使用按位AND运算符。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|786170|​|786171|function+oddOrEven(x)+{
++return+(+x+&+1+)+?+"odd"+:+"even";
}

function+checkNumber(argNumber)+{
++document.getElementById("result").innerHTML+=+"Number+"+%2B+argNumber+%2B+"+is+"+%2B+oddOrEven(argNumber);
}
+
checkNumber(17);|code-block|syntax|javascript|786172|<div+id="result"+style="font-size:150%25;text-shadow:+1px+1px+2px+#CE5937;"+></div>|786173|786174|如果你不想要一个字符串返回值，而是一个布尔型的返回值，可以使用下面的代码：|786175|var+isOdd+=+function(x)+{+return+x+&+1;+};
var+isEven++=+function(x)+{+return+!(+x+&+1+);+};|786176|entityMap|0|LINK|mutability|MUTABLE|url|https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Bitwise_Operators#.26_%2528Bitwise_AND%2529^0|4|3|4|3|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|11|8|@$9|12|A|13|B|C]]|D|@$9|14|A|15|1|16]]|E|$]]|$1|F|3|G|5|6|7|17|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|18|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|J|7|19|8|@]|D|@]|E|$K|L]]|$1|O|3|G|5|6|7|1A|8|@]|D|@]|E|$]]|$1|P|3|Q|5|6|7|1B|8|@]|D|@]|E|$]]|$1|R|3|S|5|J|7|1C|8|@]|D|@]|E|$K|L]]|$1|T|3|-4|5|6|7|1D|8|@]|D|@]|E|$]]]|U|$V|$5|W|X|Y|E|$Z|10]]]]

<p>Use the bitwise <a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Bitwise_Operators#.26_%28Bitwise_AND%29" rel="noreferrer"><code>AND</code></a> operator.</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>function oddOrEven(x) {
  return ( x &amp; 1 ) ? "odd" : "even";
}

function checkNumber(argNumber) {
  document.getElementById("result").innerHTML = "Number " + argNumber + " is " + oddOrEven(argNumber);
}
 
checkNumber(17);</code></pre>
<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div id="result" style="font-size:150%;text-shadow: 1px 1px 2px #CE5937;" &gt;&lt;/div&gt;</code></pre>
</div>
</div>
</p>

<p>If you don't want a string return value, but rather a boolean one, use this:</p>

<pre><code>var isOdd = function(x) { return x &amp; 1; };
var isEven  = function(x) { return !( x &amp; 1 ); };
</code></pre>


blocks|key|786203|text|一个你可以传递的简单函数。使用模运算符%25|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|786204|var+is_even+=+function(x)+{
++++return+!(x+%25+2);+
}

is_even(3)
false
is_even(6)
true|code-block|syntax|javascript|786205|entityMap^0|J|1|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

<p>A simple function you can pass around. Uses the modulo operator <code>%</code>:</p>

<pre><code>var is_even = function(x) {
    return !(x % 2); 
}

is_even(3)
false
is_even(6)
true
</code></pre>


blocks|key|786265|text|每个奇数除以两个余数时，余数为1，每个偶数除以零时，余数为零。因此，我们可以使用以下代码|type|unstyled|depth|inlineStyleRanges|entityRanges|data|786266|++function+checker(number)++{
+++return+number%252==0?even:odd;
+++}|code-block|syntax|javascript|786267|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>Every odd number when divided by two leaves remainder as 1 and every even number when divided by zero leaves a zero as remainder. Hence we can use this code</p>

<pre><code>  function checker(number)  {
   return number%2==0?even:odd;
   }
</code></pre>


blocks|key|1000560|text|这个怎么样..。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1000561|++++var+num+=+3+//instead+get+your+value+here
++++var+aa+=+["Even",+"Odd"];

++++alert(aa[num+%25+2]);|code-block|syntax|javascript|1000562|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>How about this...</p>

<pre><code>    var num = 3 //instead get your value here
    var aa = ["Even", "Odd"];

    alert(aa[num % 2]);
</code></pre>


blocks|key|786330|text|我就是这么做的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|786331|//Array+of+numbers
var+numbers+=+[1,+2,+3,+4,+5,+6,+7,+8,+9,+10,32,23,643,67,5876,6345,34,3453];
//Array+of+even+numbers
var+evenNumbers+=+[];
//Array+of+odd+numbers
var+oddNumbers+=+[];

function+classifyNumbers(arr){
++//go+through+the+numbers+one+by+one
++for(var+i=0;+i<=arr.length-1;+i%2B%2B){
+++++if+(arr[i]+%25+2+==+0+){
++++++++//Push+the+number+to+the+evenNumbers+array
++++++++evenNumbers.push(arr[i]);
+++++}+else+{
++++++++//Push+the+number+to+the+oddNumbers+array
++++++++oddNumbers.push(arr[i]);
+++++}
++}
}

classifyNumbers(numbers);

console.log('Even+numbers:+'+%2B+evenNumbers);
console.log('Odd+numbers:+'+%2B+oddNumbers);|code-block|syntax|javascript|786332|出于某种原因，我必须确保数组的长度小于1。如果我不这样做，我就会在oddNumbers数组的最后一个元素中得到"undefined“。|786333|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

<p>This is what I did</p>

<pre><code>//Array of numbers
var numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10,32,23,643,67,5876,6345,34,3453];
//Array of even numbers
var evenNumbers = [];
//Array of odd numbers
var oddNumbers = [];

function classifyNumbers(arr){
  //go through the numbers one by one
  for(var i=0; i&lt;=arr.length-1; i++){
     if (arr[i] % 2 == 0 ){
        //Push the number to the evenNumbers array
        evenNumbers.push(arr[i]);
     } else {
        //Push the number to the oddNumbers array
        oddNumbers.push(arr[i]);
     }
  }
}

classifyNumbers(numbers);

console.log('Even numbers: ' + evenNumbers);
console.log('Odd numbers: ' + oddNumbers);
</code></pre>

<p>For some reason I had to make sure the length of the array is less by one. When I don't do that, I get "undefined" in the last element of the oddNumbers array.</p>


blocks|key|786339|text|+++<script>
++++++++function+even_odd(){
++++++++++++var+num+=+++document.getElementById('number').value;

++++++++++++if+(+num+%25+2){
++++++++++++++++document.getElementById('result').innerHTML+=+"Entered+Number+is+Odd";
++++++++++++}
++++++++++++else{
++++++++++++++++document.getElementById('result').innerHTML+=+"Entered+Number+is+Even";
++++++++++++}
++++++++}
++++</script>
</head>
<body>
++++<center>
++++++++<div+id="error"></div>
++++++++<center>
++++++++++++<h2>+Find+Given+Number+is+Even+or+Odd+</h2>
++++++++++++<p>Enter+a+value</p>
++++++++++++<input+type="text"+id="number"+/>
++++++++++++<button+onclick="even_odd();">Check</button><br+/>
++++++++++++<div+id="result"><b></b></div>
++++++++</center>
++++</center>
</body>|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|786340|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;script&gt;
        function even_odd(){
            var num =   document.getElementById('number').value;

            if ( num % 2){
                document.getElementById('result').innerHTML = "Entered Number is Odd";
            }
            else{
                document.getElementById('result').innerHTML = "Entered Number is Even";
            }
        }
    &lt;/script&gt;
&lt;/head&gt;
&lt;body&gt;
    &lt;center&gt;
        &lt;div id="error"&gt;&lt;/div&gt;
        &lt;center&gt;
            &lt;h2&gt; Find Given Number is Even or Odd &lt;/h2&gt;
            &lt;p&gt;Enter a value&lt;/p&gt;
            &lt;input type="text" id="number" /&gt;
            &lt;button onclick="even_odd();"&gt;Check&lt;/button&gt;&lt;br /&gt;
            &lt;div id="result"&gt;&lt;b&gt;&lt;/b&gt;&lt;/div&gt;
        &lt;/center&gt;
    &lt;/center&gt;
&lt;/body&gt;
</code></pre>


blocks|key|786370|text|我会实现这个来返回一个布尔值：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|786371|function+isOdd+(n)+{
++++return+!!(n+%25+2);
++++//+or+((n+%25+2)+!==+0).
}|code-block|syntax|javascript|786372|它对无符号数字和有符号数字都有效。当模数返回-1或1时，它将被转换为true。|offset|length|style|CODE|786373|非模数解：|786374|var+is_finite+=+isFinite;
var+is_nan+=+isNaN;

function+isOdd+(discriminant)+{
++++if+(is_nan(discriminant)+&&+!is_finite(discriminant))+{
++++++++return+false;
++++}

++++//+Unsigned+numbers
++++if+(discriminant+>=+0)+{
++++++++while+(discriminant+>=+1)+discriminant+-=+2;

++++//+Signed+numbers
++++}+else+{
++++++++if+(discriminant+===+-1)+return+true;
++++++++while+(discriminant+<=+-1)+discriminant+%2B=+2;
++++}

++++return+!!discriminant;
}|786375|entityMap^0|0|0|M|2|P|1|Y|4|0|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]]|$1|G|3|H|5|6|7|U|8|@$I|V|J|W|K|L]|$I|X|J|Y|K|L]|$I|Z|J|10|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|11|8|@]|9|@]|A|$]]|$1|O|3|P|5|D|7|12|8|@]|9|@]|A|$E|F]]|$1|Q|3|-4|5|6|7|13|8|@]|9|@]|A|$]]]|R|$]]

<p>I'd implement this to return a boolean:</p>

<pre><code>function isOdd (n) {
    return !!(n % 2);
    // or ((n % 2) !== 0).
}
</code></pre>

<p>It'll work on both unsigned and signed numbers. When the modulus return <code>-1</code> or <code>1</code> it'll get translated to <code>true</code>.</p>

<p>Non-modulus solution:</p>

<pre><code>var is_finite = isFinite;
var is_nan = isNaN;

function isOdd (discriminant) {
    if (is_nan(discriminant) &amp;&amp; !is_finite(discriminant)) {
        return false;
    }

    // Unsigned numbers
    if (discriminant &gt;= 0) {
        while (discriminant &gt;= 1) discriminant -= 2;

    // Signed numbers
    } else {
        if (discriminant === -1) return true;
        while (discriminant &lt;= -1) discriminant += 2;
    }

    return !!discriminant;
}
</code></pre>


blocks|key|1000701|text|使用%25可以帮助你做到这一点……|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1000702|您可以创建几个函数来为您完成此操作...我更喜欢在Javascript中没有附加到Number的分离函数，比如它还检查你是否传递了number：|1000703|奇怪的功能：|1000704|var+isOdd+=+function(num)+{
++return+'number'!==typeof+num+?+'NaN'+:+!!(num+%25+2);
};|code-block|syntax|javascript|1000705|偶数函数：|1000706|var+isEven+=+function(num)+{
++return+isOdd(num)==='NaN'+?+isOdd(num)+:+!isOdd(num);
};|1000707|然后这样叫它：|1000708|isOdd(5);+//+true
isOdd(6);+//+false
isOdd(12);+//+false
isOdd(18);+//+false
isEven(18);+//+true
isEven('18');+//+'NaN'
isEven('17');+//+'NaN'
isOdd(null);+//+'NaN'
isEven('100');+//+true|1000709|entityMap^0|2|1|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|11|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|12|8|@]|D|@]|E|$]]|$1|J|3|K|5|L|7|13|8|@]|D|@]|E|$M|N]]|$1|O|3|P|5|6|7|14|8|@]|D|@]|E|$]]|$1|Q|3|R|5|L|7|15|8|@]|D|@]|E|$M|N]]|$1|S|3|T|5|6|7|16|8|@]|D|@]|E|$]]|$1|U|3|V|5|L|7|17|8|@]|D|@]|E|$M|N]]|$1|W|3|-4|5|6|7|18|8|@]|D|@]|E|$]]]|X|$]]

<p>Using <code>%</code> will help you to do this...</p>

<p>You can create couple of functions to do it for you... I prefer separte functions which are not attached to Number in Javascript like this which also checking if you passing number or not:</p>

<p>odd function:</p>

<pre><code>var isOdd = function(num) {
  return 'number'!==typeof num ? 'NaN' : !!(num % 2);
};
</code></pre>

<p>even function:</p>

<pre><code>var isEven = function(num) {
  return isOdd(num)==='NaN' ? isOdd(num) : !isOdd(num);
};
</code></pre>

<p>and call it like this:</p>

<pre><code>isOdd(5); // true
isOdd(6); // false
isOdd(12); // false
isOdd(18); // false
isEven(18); // true
isEven('18'); // 'NaN'
isEven('17'); // 'NaN'
isOdd(null); // 'NaN'
isEven('100'); // true
</code></pre>


blocks|key|786449|text|现代javascript中的一种更函数式的方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|786450|const+NUMBERS+=+"nul+one+two+three+four+five+six+seven+ocho+nueve".split("+")

const+negate+=+f=>+(...args)=>+!f(...args)
const+isOdd++=+n=>+NUMBERS[n+%25+10].indexOf("e")!=-1
const+isEven+=+negate(isOdd)|code-block|syntax|javascript|786451|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 more functional approach in modern javascript:</p>

<pre><code>const NUMBERS = "nul one two three four five six seven ocho nueve".split(" ")

const negate = f=&gt; (...args)=&gt; !f(...args)
const isOdd  = n=&gt; NUMBERS[n % 10].indexOf("e")!=-1
const isEven = negate(isOdd)
</code></pre>


blocks|key|786463|text|使用逐位编码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|786464|var+isEven=n=>(n&1)?"odd":"even";|code-block|syntax|javascript|786465|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>With bitwise, codegolfing:</p>

<pre><code>var isEven=n=&gt;(n&amp;1)?"odd":"even";
</code></pre>


blocks|key|1000804|text|ES6中的一行代码，仅仅因为它是干净的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1000805|const+isEven+=+(num)+=>+num+%25+2+==+0;|offset|length|style|CODE|1000806|entityMap^0|0|0|11|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

<p>One liner in ES6 just because it's clean.</p>

<p><code>const isEven = (num) =&gt; num % 2 == 0;</code></p>


blocks|key|1000840|text|这适用于数组：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1000841|function+evenOrOdd(numbers)+{
++const+evenNumbers+=+[];
++const+oddNumbers+=+[];
++numbers.forEach(number+=>+{
++++if+(number+%25+2+===+0)+{
++++++evenNumbers.push(number);
++++}+else+{
++++++oddNumbers.push(number);
++++}
++});

++console.log("Even:+"+%2B+evenNumbers+%2B+"\nOdd:+"+%2B+oddNumbers);
}

evenOrOdd([1,+4,+9,+21,+41,+92]);|code-block|syntax|javascript|1000842|这应该注销:+4,92+1,9,21,41|1000843|只需要一个数字：|1000844|function+evenOrOdd(number)+{
++if+(number+%25+2+===+0)+{
++++return+"even";
++}

++return+"odd";
}

console.log(evenOrOdd(4));|1000845|这甚至应该输出到控制台|1000846|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|T|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|U|8|@]|9|@]|A|$E|F]]|$1|M|3|N|5|6|7|V|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

<p>this works for arrays:</p>

<pre><code>function evenOrOdd(numbers) {
  const evenNumbers = [];
  const oddNumbers = [];
  numbers.forEach(number =&gt; {
    if (number % 2 === 0) {
      evenNumbers.push(number);
    } else {
      oddNumbers.push(number);
    }
  });

  console.log("Even: " + evenNumbers + "\nOdd: " + oddNumbers);
}

evenOrOdd([1, 4, 9, 21, 41, 92]);
</code></pre>

<p>this should log out:
4,92
1,9,21,41</p>

<p>for just a number:</p>

<pre><code>function evenOrOdd(number) {
  if (number % 2 === 0) {
    return "even";
  }

  return "odd";
}

console.log(evenOrOdd(4));
</code></pre>

<p>this should output even to the console</p>


blocks|key|1000854|text|在ES6中：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1000855|const+isOdd+=+num+=>+num+%25+2+==+1;|code-block|syntax|javascript|1000856|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>In ES6:</p>
<pre><code>const isOdd = num =&gt; num % 2 == 1;
</code></pre>


blocks|key|786579|text|判断数字是否为奇数的方法|type|unstyled|depth|inlineStyleRanges|entityRanges|data|786580|​|786581|let+numbers+=+[11,+20,+2,+5,+17,+10];

let+n+=+numbers.filter((ele)+=>+ele+%25+2+!=+0);

console.log(n);|code-block|syntax|javascript|786582|786583|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>A Method to know if the number is odd</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>let numbers = [11, 20, 2, 5, 17, 10];

let n = numbers.filter((ele) =&gt; ele % 2 != 0);

console.log(n);</code></pre>
</div>
</div>
</p>


blocks|key|1000909|text|使用filter()方法的另一个示例：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1000910|let+even+=+arr.filter(val+=>+{
++return+val+%25+2+===+0;
});
//+even+=+[2,4,6]|code-block|syntax|javascript|1000911|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>Another example using the filter() method:</p>
<pre><code>let even = arr.filter(val =&gt; {
  return val % 2 === 0;
});
// even = [2,4,6]
</code></pre>


blocks|key|1000944|text|如果为奇数，则返回true|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1000945|function+isOdd(n)+{
++++return+Math.abs(n)%252===1;
}|code-block|syntax|javascript|1000946|如果为even，则返回true|1000947|function+isEven(n)+{
++++return+Math.abs(n)%252!==1;
}|1000948|我在得到负数的情况下使用了Math.abs()|1000949|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

<p>Return true if odd</p>
<pre><code>function isOdd(n) {
    return Math.abs(n)%2===1;
}
</code></pre>
<p>Return true if even</p>
<pre><code>function isEven(n) {
    return Math.abs(n)%2!==1;
}
</code></pre>
<p>I used Math.abs() in case of getting a negative number</p>


<p>Can anyone point me to some code to determine if a number in JavaScript is even or odd?</p>


How to determine if a number is odd in JavaScript

谁能给我一些代码来判断JavaScript中的数字是偶数还是奇数？

问如何在JavaScript中判断数字是否为奇数
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