php如何去除超链接

$str=preg_replace("/<a[^>]*href=[^>]*>|</[^a]*a[^>]*>/i","",$content);

ereg_replace("<a [^>]*>|</a>","",$content);

$find="this string is my find"; 
$string='<font color="red">这段内容将要被替换掉</font>';//将超链接替换成的内容 
echo ereg_replace('<a([^>]*)>([^<]*'.$find.'[^>]*)</a>','<font color="red">2</font>',$content);

//方法一 
preg_match_all('/<(a|a)[s]{0,1}[w=":()]*>[nrn]*(check user)[nrn]*</(a|a)>/i',$string,$matches); 
 
//方法二 
preg_match_all('/<a[dd]*>check user</a>/i',$string,$matches); 
print_r($matches); 
 
//方法三 
preg_match_all('/<a[^>]*>[^<]*</a>/i',$string,$matches); 
print_r($matches); 
 
//方法四 
preg_match_all('/<a.+?>check user</a>/is',$str,$arr); 
print_r($arr);