How to replace all strings with php regular expression

How to implement regular php replacement of all strings: first use the preg_match() function to match all strings; then traverse the array; then use the strpos function to calculate the position; finally use the substr_replace function to replace the string at the specified position. .

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php Replace multiple different characters in a string

There are two functions that can replace strings

The idea is to use the preg_match() function to first match all strings, traverse the array strpos(), calculate the position, and use substr_replace() to replace the specified position. String.

For example: replace all a tags in an html page

function getAarr($str){
    //拿出网页中所有a标签放到数组
    $reg1="/<a[\s\S]*?>[\s\S]*?<\/a>/";
    $aarray = array();//这个存放的就是正则匹配出来的所有《a》标签数组
    preg_match_all($reg1,$str,$aarray);
    return $aarray[0];
}
function replace($sou_str,$urls){
    $arr_a = getAarr($sou_str);
    shuffle($urls);
    foreach($arr_a as $i=> $one){
        $begin = strpos($sou_str,$one);//开始位置
        $length = strlen($one);//字符串长度
        if(!isset($urls[$i])){
            $urls[$i][&#39;name&#39;] = str_replace(" ","",strip_tags($one));
            $urls[$i][&#39;url&#39;] = "./?".$urls[$i][&#39;name&#39;];
            $urls[$i] = "<a target=&#39;_blank&#39; href=&#39;".$urls[$i][&#39;url&#39;]."&#39; title=&#39;".$urls[$i][&#39;name&#39;]."&#39;>".$urls[$i][&#39;name&#39;]."</a>";
        }else{
            $urls[$i] = "<a target=&#39;_blank&#39; href=&#39;".$urls[$i][&#39;url&#39;]."&#39; title=&#39;".$urls[$i][&#39;name&#39;]."&#39;>".$urls[$i][&#39;name&#39;]."</a>";
        }
        if ($begin!==false){
            $sou_str = substr_replace($sou_str,$urls[$i],$begin,$length);
        }
    }
    return $sou_str;
}

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