这段代码检查PHP中的数字是奇数还是偶数。在这个例子中，$a是2，你得到偶数。如果你需要奇数，那么改变$a值

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

所有偶数除以2都得整数

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

这段代码检查PHP中的数字是奇数还是偶数。在这个例子中，$a是2，你得到偶数。如果你需要奇数，那么改变$a值

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

<?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";
?>

因此，输出将是Odd

//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.";
}

$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 . "<br/>";
}

$after = microtime(true);

echo $after-$before. 'seconds';