PHP 正则表达式语法，请见米扑博客之前总结的：PHP 正则表达式

本文直接给出PHP的正则表达式过滤常用标签 

<?php
	$str = preg_replace("/\s+/", " ", $str); 				//过滤多余回车
	$str = preg_replace("/<[ ]+/si","<", $str); 			//过滤<__("<"号后面带空格)
	$str = preg_replace("/<\!–.*?–>/si","", $str); 			//注释

	$str = preg_replace("/<(\!.*?)>/si","", $str); 			//过滤DOCTYPE
	$str = preg_replace("/<(\/?html.*?)>/si","", $str); 	//过滤html标签
	$str = preg_replace("/<(\/?br.*?)>/si","", $str); 		//过滤br标签

	$str = preg_replace("/<(\/?head.*?)>/si","", $str); 	//过滤head标签
	$str = preg_replace("/<(\/?meta.*?)>/si","", $str); 	//过滤meta标签
	$str = preg_replace("/<(\/?body.*?)>/si","", $str); 	//过滤body标签
	$str = preg_replace("/<(\/?link.*?)>/si","", $str); 	//过滤link标签
	$str = preg_replace("/<(\/?form.*?)>/si","", $str); 	//过滤form标签

	$str = preg_replace("/cookie/si","COOKIE", $str); 							//过滤COOKIE标签
	$str = preg_replace("/<(applet.*?)>(.*?)<(\/applet.*?)>/si","", $str); 		//过滤applet标签
	$str = preg_replace("/<(\/?applet.*?)>/si","", $str); 						//过滤applet标签
	$str = preg_replace("/<(style.*?)>(.*?)<(\/style.*?)>/si","", $str); 		//过滤style标签
	$str = preg_replace("/<(\/?style.*?)>/si","", $str); 						//过滤style标签
	$str = preg_replace("/<(title.*?)>(.*?)<(\/title.*?)>/si","", $str); 		//过滤title标签
	$str = preg_replace("/<(\/?title.*?)>/si","", $str); 						//过滤title标签
	
	$str = preg_replace("/<(object.*?)>(.*?)<(\/object.*?)>/si","", $str); 		//过滤object标签
	$str = preg_replace("/<(\/?objec.*?)>/si","", $str); 						//过滤object标签
	$str = preg_replace("/<(noframes.*?)>(.*?)<(\/noframes.*?)>/si","", $str); 	//过滤noframes标签
	$str = preg_replace("/<(\/?noframes.*?)>/si","", $str); 					//过滤noframes标签
	$str = preg_replace("/<(i?frame.*?)>(.*?)<(\/i?frame.*?)>/si","", $str); 	//过滤frame标签
	$str = preg_replace("/<(\/?i?frame.*?)>/si","", $str); 						//过滤frame标签
	$str = preg_replace("/<(script.*?)>(.*?)<(\/script.*?)>/si","", $str); 		//过滤script标签
	$str = preg_replace("/<(\/?script.*?)>/si","", $str); 			//过滤script标签
	$str = preg_replace("/javascript/si","Javascript", $str); 		//过滤script标签
	$str = preg_replace("/vbscript/si","Vbscript", $str); 			//过滤script标签
	$str = preg_replace("/on([a-z]+)\s*=/si","On\\1=", $str); 		//过滤script标签
	$str = preg_replace("/&#/si","&＃", $str); 						//过滤script标签
?>

 

更多常见正则表达式，请见站长工具：http://tool.chinaz.com/tools/regexgenerate

 

 

参考推荐：

PHP 正则表达式

PHP 正则匹配提取网页内容

PHP 判断数字，字母，特殊符号，中文

PHP 获取网页标题(title)、描述(description)、关键字(keywords)等meta信息​