试试下面的例子就明白了算术运算符操作。复制并粘贴到test.php文件，下面的PHP程序，并保存它在PHP服务器的文档根目录并使用浏览器浏览。
<html>
<head><title>Arithmetical Operators</title><head>
<body>
<?php
$a = 42;
$b = 20;
$c = $a + $b;
echo "Addtion Operation Result: $c <br/>";
$c = $a - $b;
echo "Substraction Operation Result: $c <br/>";
$c = $a * $b;
echo "Multiplication Operation Result: $c <br/>";
$c = $a / $b;
echo "Division Operation Result: $c <br/>";
$c = $a % $b;
echo "Modulus Operation Result: $c <br/>";
$c = $a++;
echo "Increment Operation Result: $c <br/>";
$c = $a--;
echo "Decrement Operation Result: $c <br/>";
?>
</body>
</html>
这将产生以下结果
Addtion Operation Result: 62 Substraction Operation Result: 22 Multiplication Operation Result: 840 Division Operation Result: 2.1 Modulus Operation Result: 2 Increment Operation Result: 42 Decrement Operation Result: 43
