PHP eval() 函数

实例

把字符串当成 PHP 代码来计算：

 <?php
$string = "beautiful";
 $time = "winter";

 $str = 'This is a $string $time morning!';
 echo $str. "<br>";

 eval("$str = "$str";");
 echo $str;
 ?>

The output of the code above will be:

 This is a $string $time morning!
 This is a beautiful winter morning!