<?php function replace_url ($content) { if (empty($content)) return; //给URL地址加上 <a> 链接 $preg = '/(?:http://)?([w.]+[w/]*.[w.]+[w/]*??[w=&+\%]*)/is'; $content = preg_replace($preg, '<a href="http://1" target="_blank">1</a>', $content); return $content; } echo replace_url('百度:http://blog.csdn.net/moqiang02'); ?>