說明
這將跳過錨標記中的所有其他屬性,即使它們的值看起來像嵌套在值中的屬性。
<a(?=\s|>) # validate this is an anchor tag
(?! # start look ahead ! must not contain, = must contain
(?:[^>=]|='[^']*'|="[^"]*"|=[^'"][^\s>]*)*? # move through tag, skipping over quoted or non quoted values
\shref="[^"]*(?:jpg|png|gif)" # find href, capture value including quotes if they exist
) # end look ahead
[^>]*>.*?<\/a> # capture the entire to the close tag
PHP代碼示例:
示例文本
音符第二行
<a href="http://mysite.com">My Site</a>
<a wrongtag=" href='http://mysite.com/image.jpg' " href="http://mysite.com">My Site</a>
<a href="http://mysite.com/image.jpg"><img src="http://mysite.com/image.jpg"/></a>
<a href="http://mysite.com/image.gif"><img src="http://mysite.com/image.gif"/></a>
<a href="http://yoursite.com">Your Site</a>
代碼
<?php
$sourcestring="your source string";
echo preg_replace('/<a(?=\s|>)
(?! # start look ahead ! must not contain, = must contain
(?:[^>=]|=\'[^\']*\'|="[^"]*"|=[^\'"][^\s>]*)*? # move through tag, skipping over quoted or non quoted values
\shref="[^"]*(?:jpg|png|gif)" # find href, capture value including quotes if they exist
) # end look ahead
[^>]*>.*?<\/a> # actually capture the string
/imsx','',$sourcestring);
?>
匹配
[0] => <a href="http://mysite.com/image.jpg"><img src="http://mysite.com/image.jpg"/></a>
[1] => <a href="http://mysite.com/image.gif"><img src="http://mysite.com/image.gif"/></a>
@mario,我已經試過非常多,Google搜索和搜索在這裏上。但我沒有發現我正在尋找。 –
[解析和處理HTML/XML?]的可能的重複(http://stackoverflow.com/questions/3577641/parsing-and-processing-html-xml) – Quentin