非常全的PHP处理html标签的常用正则表达式。正则表达式非常有用，但是总感觉精通的人不是很多，可能现在都是用集成函数处理的原因了吧。不精通行，但也得会用。整理下常用的PHP处理html标签的常用正则表达式，希望对大家有所帮助。
01 $str=preg_replace(“/\s+/”, ” “, $str); //过滤多余回车
02 $str=preg_replace(“/<[ ]+/si”,”<“,$str); //过滤<__(“<“号后面带空格)
04 $str=preg_replace(“/<\!–.*?–>/si”,””,$str); //注释
05 $str=preg_replace(“/<(\!.*?)>/si”,””,$str); //过滤DOCTYPE
06 $str=preg_replace(“/<(\/?html.*?)>/si”,””,$str); //过滤html标签
07 $str=preg_replace(“/<(\/?head.*?)>/si”,””,$str); //过滤head标签
08 $str=preg_replace(“/<(\/?meta.*?)>/si”,””,$str); //过滤meta标签
09 $str=preg_replace(“/<(\/?body.*?)>/si”,””,$str); //过滤body标签
10 $str=preg_replace(“/<(\/?link.*?)>/si”,””,$str); //过滤link标签
11 $str=preg_replace(“/<(\/?form.*?)>/si”,””,$str); //过滤form标签
12 $str=preg_replace(“/cookie/si”,”COOKIE”,$str); //过滤COOKIE标签
13
14 $str=preg_replace(“/<(applet.*?)>(.*?)<(\/applet.*?)>/si”,””,$str); //过滤applet标签
15 $str=preg_replace(“/<(\/?applet.*?)>/si”,””,$str); //过滤applet标签
16
17 $str=preg_replace(“/<(style.*?)>(.*?)<(\/style.*?)>/si”,””,$str); //过滤style标签
18 $str=preg_replace(“/<(\/?style.*?)>/si”,””,$str); //过滤style标签
19
20 $str=preg_replace(“/<(title.*?)>(.*?)<(\/title.*?)>/si”,””,$str); //过滤title标签
21 $str=preg_replace(“/<(\/?title.*?)>/si”,””,$str); //过滤title标签
22
23 $str=preg_replace(“/<(object.*?)>(.*?)<(\/object.*?)>/si”,””,$str); //过滤object标签
24 $str=preg_replace(“/<(\/?objec.*?)>/si”,””,$str); //过滤object标签
25
26 $str=preg_replace(“/<(noframes.*?)>(.*?)<(\/noframes.*?)>/si”,””,$str); //过滤noframes标签
27 $str=preg_replace(“/<(\/?noframes.*?)>/si”,””,$str); //过滤noframes标签
28
29 $str=preg_replace(“/<(i?frame.*?)>(.*?)<(\/i?frame.*?)>/si”,””,$str); //过滤frame标签
30 $str=preg_replace(“/<(\/?i?frame.*?)>/si”,””,$str); //过滤frame标签
31
32 $str=preg_replace(“/<(script.*?)>(.*?)<(\/script.*?)>/si”,””,$str); //过滤script标签
33 $str=preg_replace(“/<(\/?script.*?)>/si”,””,$str); //过滤script标签
34 $str=preg_replace(“/javascript/si”,”Javascript”,$str); //过滤script标签
35 $str=preg_replace(“/vbscript/si”,”Vbscript”,$str); //过滤script标签
36 $str=preg_replace(“/on([a-z]+)\s*=/si”,”On\\1=”,$str); //过滤script标签
37 $str=preg_replace(“/&#/si”,”&＃”,$str); //过滤script标签，如javAsCript:alert(‘aabb)