blocks|key|4737232|text|另一种选择是简单的比特检查。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4737233|n+&+1|code-block|syntax|javascript|4737234|例如：|4737235|if+(+$num+&+1+)+{
++//odd
}+else+{
++//even
}|4737236|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|$]]

Another option is a simple bit checking.

<pre><code>n &amp; 1
</code></pre>

for example:

<pre><code>if ( $num &amp; 1 ) {
 //odd
} else {
 //even
}
</code></pre>

blocks|key|793832|text|是，使用模式|type|unstyled|depth|inlineStyleRanges|entityRanges|data|793833|$even+=+($num+%25+2+==+0);
$odd+=+($num+%25+2+!=+0);|code-block|syntax|javascript|793834|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|$]]

Yes using the mod

<pre><code>$even = ($num % 2 == 0);
$odd = ($num % 2 != 0);
</code></pre>

blocks|key|4737590|text|虽然所有的答案都是正确的，但一行简单的解决方案是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4737591|$check+=+9;|code-block|syntax|javascript|4737592|以下任一项：|4737593|echo+($check+&+1+?+'Odd'+:+'Even');|4737594|或者：|4737595|echo+($check+%25+2+?+'Odd'+:+'Even');|4737596|效果非常好。|4737597|entityMap^0|0|0|0|0|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]]|$1|G|3|H|5|6|7|U|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

While all of the answers are good and correct, simple solution in one line is:

<pre><code>$check = 9;
</code></pre>

either:

<pre><code>echo ($check &amp; 1 ? 'Odd' : 'Even');
</code></pre>

or:

<pre><code>echo ($check % 2 ? 'Odd' : 'Even');
</code></pre>

works very well.

blocks|key|4737317|text|(bool)($number+&+1)|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4737318|或|unstyled|4737319|(bool)(~+$number+&+1)|4737320|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>(bool)($number &amp; 1)
</code></pre>

or 

<pre><code>(bool)(~ $number &amp; 1)
</code></pre>

blocks|key|3122276|text|我做了一些测试，发现在mod，is_int和&-operator中，mod是最快的，紧随其后的是&-运算符。is_int比mod慢近4倍。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3122277|我使用以下代码进行测试：|3122278|$number+=+13;

$before+=+microtime(true);
for+($i=0;+$i<100000;+$i%2B%2B)+{
++++$test+=+($number%252?true:false);
}
$after+=+microtime(true);

echo+$after-$before."+seconds+mod ";

$before+=+microtime(true);
for+($i=0;+$i<100000;+$i%2B%2B)+{
++++$test+=+(!is_int($number/2)?true:false);
}
$after+=+microtime(true);

echo+$after-$before."+seconds+is_int ";

$before+=+microtime(true);
for+($i=0;+$i<100000;+$i%2B%2B)+{
++++$test+=+($number&1?true:false);
}
$after+=+microtime(true);

echo+$after-$before."+seconds+&+operator ";|code-block|syntax|javascript|3122279|我得到的结果是相当一致的。下面是一个示例：|3122280|0.041879177093506+seconds+mod
0.15969395637512+seconds+is_int
0.044223070144653+seconds+&+operator|3122281|entityMap^0|F|6|M|1|1I|6|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|11|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|12|8|@]|D|@]|E|$K|L]]|$1|Q|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|R|$]]

I did a bit of testing, and found that between mod, <code>is_int</code> and the <code>&amp;</code>-operator, mod is the fastest, followed closely by the &amp;-operator.
<code>is_int</code> is nearly 4 times slower than mod.

I used the following code for testing purposes:
 

<pre><code>$number = 13;

$before = microtime(true);
for ($i=0; $i&lt;100000; $i++) {
 $test = ($number%2?true:false);
}
$after = microtime(true);

echo $after-$before." seconds mod&lt;br&gt;";

$before = microtime(true);
for ($i=0; $i&lt;100000; $i++) {
 $test = (!is_int($number/2)?true:false);
}
$after = microtime(true);

echo $after-$before." seconds is_int&lt;br&gt;";

$before = microtime(true);
for ($i=0; $i&lt;100000; $i++) {
 $test = ($number&amp;1?true:false);
}
$after = microtime(true);

echo $after-$before." seconds &amp; operator&lt;br&gt;";
</code></pre>

The results I got were pretty consistent. Here's a sample:

<pre><code>0.041879177093506 seconds mod
0.15969395637512 seconds is_int
0.044223070144653 seconds &amp; operator
</code></pre>

blocks|key|790040|text|另一种选择是检查最后一个数字是否为偶数：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|790041|$value+=+"1024";//+A+Number
$even+=+array(0,+2,+4,+6,+8);
if(in_array(substr($value,+-1),$even)){
++//+Even+Number
}else{
++//+Odd+Number
}|code-block|syntax|javascript|790042|或者为了更快，请使用isset()而不是array_search：|offset|length|style|CODE|790043|$value+=+"1024";//+A+Number
$even+=+array(0+=>+1,+2+=>+1,+4+=>+1,+6+=>+1,+8+=>+1);
if(isset($even[substr($value,+-1)]){
++//+Even+Number
}else{
++//+Odd+Number
}|790044|或者让它更快地运行+(+)：|790045|$even+=+array(0,+2,+4,+6,+8);
if(in_array(substr($number,+-1),$even)){
++//+Even+Number
}else{
++//+Odd+Number
}|790046|这是time+test作为我的发现的证据。|790047|entityMap|0|LINK|mutability|MUTABLE|url|https://eval.in/528257|1|https://eval.in/287118^0|0|0|A|7|K|C|0|0|B|1|0|0|0|2|9|1|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|16|8|@$I|17|J|18|K|L]|$I|19|J|1A|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|1B|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|1C|8|@]|9|@$I|1D|J|1E|1|1F]]|A|$]]|$1|Q|3|R|5|D|7|1G|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|1H|8|@]|9|@$I|1I|J|1J|1|1K]]|A|$]]|$1|U|3|-4|5|6|7|1L|8|@]|9|@]|A|$]]]|V|$W|$5|X|Y|Z|A|$10|11]]|12|$5|X|Y|Z|A|$10|13]]]]

Another option is to check if the last digit is an even number :

<pre><code>$value = "1024";// A Number
$even = array(0, 2, 4, 6, 8);
if(in_array(substr($value, -1),$even)){
 // Even Number
}else{
 // Odd Number
}
</code></pre>

Or to make it faster, use <code>isset()</code> instead of <code>array_search</code> :

<pre><code>$value = "1024";// A Number
$even = array(0 =&gt; 1, 2 =&gt; 1, 4 =&gt; 1, 6 =&gt; 1, 8 =&gt; 1);
if(isset($even[substr($value, -1)]){
 // Even Number
}else{
 // Odd Number
}
</code></pre>

Or to make it more faster (<a href="https://eval.in/528257" rel="nofollow">beats <code>mod operator</code> at times</a>) :

<pre><code>$even = array(0, 2, 4, 6, 8);
if(in_array(substr($number, -1),$even)){
 // Even Number
}else{
 // Odd Number
}
</code></pre>

Here is the <a href="https://eval.in/287118" rel="nofollow">time test</a> as a proof to my findings.

blocks|key|4737561|text|PHP会自动将null和空字符串转换为零。这种情况也会发生在模数上。因此，代码将|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4737562|$number+%25+2+==+0+or+!($number+&+1)|code-block|syntax|javascript|4737563|如果值$number+=+'‘或$number+=+null，则结果为true。为此，我对它进行了更多的扩展：|4737564|function+testEven($pArg){
++++if(is_int($pArg)+===+true){
++++++++$p+=+($pArg+%25+2);
++++++++if($p+===+0){
++++++++++++print+"The+input+'".$pArg."'+is+even. ";
++++++++}else{
++++++++++++print+"The+input+'".$pArg."'+is+odd. ";
++++++++}
++++}else{
++++++++print+"The+input+'".$pArg."'+is+not+a+number. ";
++++}
}

The+print+is+there+for+testing+purposes,+hence+in+practice+it+becomes:
function+testEven($pArg){
++++if(is_int($pArg)===+true){
++++++++return+$pArg%252;
++++}
++++return+false;
}|4737565|对于任何奇数，此函数返回1；对于任何偶数，此函数返回0；如果不是数字，则返回false。我总是写===+true或===+false来让我自己(和其他程序员)知道测试是按照预期进行的。|4737566|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|$]]

PHP is converting null and an empty string automatically to a zero. That happens with modulo as well. Therefor will the code
<pre><code>$number % 2 == 0 or !($number &amp; 1)
</code></pre>
with value $number = '' or $number = null
result in true.
I test it therefor somewhat more extended:
<pre><code>function testEven($pArg){
 if(is_int($pArg) === true){
 $p = ($pArg % 2);
 if($p === 0){
 print &quot;The input '&quot;.$pArg.&quot;' is even.&lt;br&gt;&quot;;
 }else{
 print &quot;The input '&quot;.$pArg.&quot;' is odd.&lt;br&gt;&quot;;
 }
 }else{
 print &quot;The input '&quot;.$pArg.&quot;' is not a number.&lt;br&gt;&quot;;
 }
}

The print is there for testing purposes, hence in practice it becomes:
function testEven($pArg){
 if(is_int($pArg)=== true){
 return $pArg%2;
 }
 return false;
}
</code></pre>
This function returns 1 for any odd number, 0 for any even number and false when it is not a number. I always write === true or === false to let myself (and other programmers) know that the test is as intended.

blocks|key|789929|text|所有偶数除以2将得到一个整数|type|unstyled|depth|inlineStyleRanges|entityRanges|data|789930|$number+=+4;
if(is_int($number/2))
{
+++echo("Integer");
}
else
{
+++echo("Not+Integer");
}|code-block|syntax|javascript|789931|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|$]]

All even numbers divided by 2 will result in an integer

<pre><code>$number = 4;
if(is_int($number/2))
{
 echo("Integer");
}
else
{
 echo("Not Integer");
}
</code></pre>

blocks|key|790080|text|这段代码检查PHP中的数字是奇数还是偶数。在这个例子中，$a是2，你得到的是偶数。如果需要odd，则更改$a的值|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|790081|$a=2;
if($a+%252+==+0){
++++echo+"<h3>This+Number+is+$a+Even</h3>";
}else{
++++echo+"<h3>This+Number+is+$a+Odd</h3>";
}|code-block|syntax|javascript|790082|entityMap^0|S|2|V|1|1G|2|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|U|8|@]|D|@]|E|$]]]|L|$]]

This code checks if the number is odd or even in PHP. In the example <code>$a</code> is <code>2</code> and you get even number. If you need odd then change the <code>$a</code> value

<pre><code>$a=2;
if($a %2 == 0){
 echo "&lt;h3&gt;This Number is &lt;b&gt;$a&lt;/b&gt; Even&lt;/h3&gt;";
}else{
 echo "&lt;h3&gt;This Number is &lt;b&gt;$a&lt;/b&gt; Odd&lt;/h3&gt;";
}
</code></pre>

blocks|key|3122321|text|我假设已经有了一个计数器。在循环结束时递增的$i中，这对我使用速记查询很有效。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3122322|$row_pos+=+($i+&+1)+?+'odd'+:+'even';|code-block|syntax|javascript|3122323|那么这是做什么的，它查询我们所做的语句，本质上$i是奇怪的，取决于它是真还是假，将决定返回什么。返回值填充我们的变量$row_pos|3122324|我使用它是将它放在foreach循环中，就在我需要它之前，这使得它成为一个非常有效的给我提供适当类名的线程，这是因为我已经有了一个id的计数器，可以在程序后面使用。这是我将如何使用这一部分的一个简短示例。|3122325|<div+class='row-{$row_pos}'>+random+data+<div>|3122326|这为我在每一行上提供了奇数和偶数类，这样我就可以使用正确的类，并将打印的结果沿页面向下条带化。|3122327|我使用的完整示例注意id应用了计数器，类应用了我的奇偶结果：|3122328|$i=0;
foreach+($a+as+$k+=>+$v)+{

++++$row_pos+=+($i+&+1)+?+'odd'+:+'even';
++++echo+"<div+id='A{$i}'+class='row-{$row_pos}'>{$v['f_name']}+{$v['l_name']}+-+{$v['amount']}+-+{$v['date']}</div>\n";

$i%2B%2B;
}|3122329|总而言之，这给了我一个非常简单的方法来创建一个漂亮的表。|3122330|entityMap^0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|Z|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|10|8|@]|9|@]|A|$E|F]]|$1|M|3|N|5|6|7|11|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|12|8|@]|9|@]|A|$]]|$1|Q|3|R|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|S|3|T|5|6|7|14|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|V|$]]

I am making an assumption that there is a counter already in place. in $i which is incremented at the end of a loop, This works for me using a shorthand query.

<pre><code>$row_pos = ($i &amp; 1) ? 'odd' : 'even';
</code></pre>

So what does this do, well it queries the statement we are making in essence $i is odd, depending whether its true or false will decide what gets returned. The returned value populates our variable $row_pos

My use of this is to place it inside the foreach loop, right before i need it, This makes it a very efficient one liner to give me the appropriate class names, this is because i already have a counter for the id's to make use of later in the program. This is a brief example of how i will use this part.

<pre><code>&lt;div class='row-{$row_pos}'&gt; random data &lt;div&gt;
</code></pre>

This gives me odd and even classes on each row so i can use the correct class and stripe my printed results down the page.

The full example of what i use note the id has the counter applied to it and the class has my odd/even result applied to it.:

<pre><code>$i=0;
foreach ($a as $k =&gt; $v) {

 $row_pos = ($i &amp; 1) ? 'odd' : 'even';
 echo "&lt;div id='A{$i}' class='row-{$row_pos}'&gt;{$v['f_name']} {$v['l_name']} - {$v['amount']} - {$v['date']}&lt;/div&gt;\n";

$i++;
}
</code></pre>

in summary, this gives me a very simple way to create a pretty table.

blocks|key|4737599|text|尝尝这个,|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4737600|$number+=+10;
+switch+($number%252)
+{
+case+0:
+echo+"It's+even";
+break;
+default:
+echo+"It's+odd";
+}|code-block|syntax|javascript|4737601|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|$]]

Try this,

<pre><code>$number = 10;
 switch ($number%2)
 {
 case 0:
 echo "It's even";
 break;
 default:
 echo "It's odd";
 }
</code></pre>

blocks|key|5020431|text|如果奇数，则$number+%252+=1...所以不用用甚至不用...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5020432|$number+=+27;

if+($number+%25+2+==+1)+{
++print+"It's+odd";
}|code-block|syntax|javascript|5020433|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|$]]

$number %2 = 1 if odd... so don't have to use not even...
<pre><code>$number = 27;

if ($number % 2 == 1) {
 print &quot;It's odd&quot;;
}
</code></pre>

blocks|key|5020474|text|两个简单的按位函数，返回0表示False，返回1表示True。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5020475|#+is_odd:+1+for+odd+,+0+for+even
odd+=+number+&+1

#+is_even:+1+for+even+,+0+for+odd
even+=+number+&+1+%5E+1|code-block|syntax|javascript|5020476|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|$]]

Two simple bitwise functions, returning a 0 for False and 1 for True.
<pre><code># is_odd: 1 for odd , 0 for even
odd = number &amp; 1

# is_even: 1 for even , 0 for odd
even = number &amp; 1 ^ 1
</code></pre>

blocks|key|794094|text|<?php
//+Recursive+function+to+check+whether
//+the+number+is+Even+or+Odd+
function+check($number){
++++if($number+==+0)
++++++++return+1;
++++else+if($number+==+1)
++++++++return+0;
++++else+if($number<0)
++++++++return+check(-$number);
++++else
++++++++return+check($number-2);++++++++
}
++
//+Check+the+number+odd+or+even
$number+=+35;
if(check($number))
++++echo+"Even";
else
++++echo+"Odd";
?>|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|794095|因此，输出将是奇数|unstyled|offset|length|style|BOLD|794096|entityMap^0|0|7|2|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|N|8|@$G|O|H|P|I|J]]|9|@]|A|$]]|$1|K|3|-4|5|F|7|Q|8|@]|9|@]|A|$]]]|L|$]]

<pre><code>&lt;?php
// Recursive function to check whether
// the number is Even or Odd 
function check($number){
 if($number == 0)
 return 1;
 else if($number == 1)
 return 0;
 else if($number&lt;0)
 return check(-$number);
 else
 return check($number-2); 
}
 
// Check the number odd or even
$number = 35;
if(check($number))
 echo &quot;Even&quot;;
else
 echo &quot;Odd&quot;;
?&gt;
</code></pre>
So, the output will be Odd

blocks|key|4737568|text|$before+=+microtime(true);

$n+=+1000;++
$numbers+=+range(1,$n);

$cube_numbers+=+array_map('cube',$numbers);

function+cube($n){++++++
++++$msg+='even';+++++++
++++if($n%252+!=0){
++++++++$msg+=+'odd';
++++}+++++++++++++++
++++return+"The+Number+is+$n+is+".$msg;
}

foreach($cube_numbers+as+$cube){
++++echo+$cube+.+" ";
}

$after+=+microtime(true);

echo+$after-$before.+'seconds';|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4737569|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>$before = microtime(true);

$n = 1000; 
$numbers = range(1,$n);

$cube_numbers = array_map('cube',$numbers);

function cube($n){ 
 $msg ='even'; 
 if($n%2 !=0){
 $msg = 'odd';
 } 
 return "The Number is $n is ".$msg;
}

foreach($cube_numbers as $cube){
 echo $cube . "&lt;br/&gt;";
}

$after = microtime(true);

echo $after-$before. 'seconds';
</code></pre>

blocks|key|4737607|text|//checking+even+and+odd
$num+=14;

$even+=+($num+%25+2+==+0);
$odd+=+($num+%25+2+!=+0);

if($even){
++++echo+"Number+is+even.";
}+else+{
++++echo+"Number+is+odd.";
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4737608|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>//checking even and odd
$num =14;

$even = ($num % 2 == 0);
$odd = ($num % 2 != 0);

if($even){
 echo "Number is even.";
} else {
 echo "Number is odd.";
}
</code></pre>

blocks|key|5020427|text|使用#输入字段尝试此方法|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5020428|<?php
++++//checking+even+and+odd
++++echo+'<form+action=""+method="post">';
++++echo+"<input+type='text'+name='num'>\n";
++++echo+"<button+type='submit'+name='submit'>Check</button>\n";
++++echo+"</form>";

++++$num+=+0;
++++if+($_SERVER["REQUEST_METHOD"]+==+"POST")+{
++++++if+(empty($_POST["num"]))+{
++++++++$numErr+=+"<span+style+='color:+red;'>Number+is+required.";
++++++++echo+$numErr;
++++++++die();
++++++}+else+{
++++++++++$num+=+$_POST["num"];
++++++}


++++$even+=+($num+%25+2+==+0);
++++$odd+=+($num+%25+2+!=+0);
++++if+($num+>+0){
++++++++if($even){
++++++++++++echo+"Number+is+even.";
++++++++}+else+{
++++++++++++echo+"Number+is+odd.";
++++++++}
++++}+else+{
++++++++echo+"Not+a+number.";
++++}
++++}
?>|code-block|syntax|javascript|5020429|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|$]]

Try this one with #Input field 

<pre><code>&lt;?php
 //checking even and odd
 echo '&lt;form action="" method="post"&gt;';
 echo "&lt;input type='text' name='num'&gt;\n";
 echo "&lt;button type='submit' name='submit'&gt;Check&lt;/button&gt;\n";
 echo "&lt;/form&gt;";

 $num = 0;
 if ($_SERVER["REQUEST_METHOD"] == "POST") {
 if (empty($_POST["num"])) {
 $numErr = "&lt;span style ='color: red;'&gt;Number is required.&lt;/span&gt;";
 echo $numErr;
 die();
 } else {
 $num = $_POST["num"];
 }


 $even = ($num % 2 == 0);
 $odd = ($num % 2 != 0);
 if ($num &gt; 0){
 if($even){
 echo "Number is even.";
 } else {
 echo "Number is odd.";
 }
 } else {
 echo "Not a number.";
 }
 }
?&gt;
</code></pre>

What is the simplest most basic way to find out if a number/variable is odd or even in PHP?
Is it something to do with mod?

I've tried a few scripts but.. google isn't delivering at the moment.

Test if number is odd or even

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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在PHP中，判断数字/变量是奇数还是偶数的最简单、最基本的方法是什么？是不是和mod有关？我试过几个脚本，但是..谷歌目前还没有交付服务。

问测试数字是奇数还是偶数
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回答 17

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问测试数字是奇数还是偶数
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