php中将html中的br换行符转换为文本输入中的换行符

function br2nl($text){
    return preg_replace('/<br\\s*?\/??>/i','',$text);
}

function br2nl($text){
    $text=preg_replace('/<br\\s*?\/??>/i',chr(13),$text);
 return preg_replace('/ /i',' ',$text);
}

function br2nl(txt){
    var re=/(<br\/>|<br>|<BR>|<BR\/>)/g;
    var s=txt.replace(re,"\n");
    return s;                                  
}