php回调函数callback函数实例

<?php

// 将文本中的年份增加一年.

$text = "April fools day is 04/01/2002\n";

$text.= "Last christmas was 12/24/2001\n";

// 回调函数

function next_year($matches)

{

  // 通常: $matches[0]是完成的匹配

  // $matches[1]是第一个捕获子组的匹配

  // 以此类推

  return $matches[1].($matches[2]+1);

}

echo preg_replace_callback(

            "|(\d{2}/\d{2}/)(\d{4})|",

            "next_year",

            $text);



?>

　　输出

April fools day is 04/01/2003

Last christmas was 12/24/2002