php实现特殊字符的替换操作

int substr_count(string haystack,string needle)

//定义敏感词数组
$array = array('骂人','肮脏','污秽');
//定义包含敏感词的字符串
$mgstr = '这是包含骂人肮脏污秽的话';
//利用循环判断字符串是否包含敏感词
for($i = 0; $i <= count($array); $i++) {
$count = substr_count($mgstr, $array);
if($count > 0) {
$info = $count;
break;
}
}
if($info > 0) {
//有敏感字符
return true;
}else{
//无敏感字符
return false;
}

mixed preg_replace ( mixed $pattern , mixed $replacement , mixed $subject [, int $limit = -1 [, int &$count ]] )

//关键词存放在.txt文件中
<?php
//自定义替换函数
function Replace($str, $filenam){
if(!($words = file_get_contents($filename))) {
//将敏感词语文本取出
die(&#39;文件获取失败!&#39;);
}
//取出成功,将字符串改成小写
$string = strtolower($str);
$word = preg_replace(&#39;/[1,2,3]\r\n|\r\n/i&#39;,&#39;&#39;,$words);
//字符串中出现文本敏感词，用特殊符号替换
$match = preg_replace(&#39;/&#39;.$word.&#39;/i&#39;,&#39;***&#39;,$string);
return $match;
}
//定义包含敏感词的字符串
$content = &#39;<a href="#">肮脏fsdf污秽d 骂人</a>&#39;
//判断是否替换成功
if($result = Replace($content, &#39;./words.txt&#39;)) {
echo $result;
echo &#39;替换成功!&#39;;
}else {
echo &#39;替换失败!&#39;;
}
?>