获取html中的文本数据

function GetHtmlText($str)
{
 $str = preg_replace("/||/isU","",$str);
  $alltext = "";
  $start = 1;
  for($i=0;$i    if($start==0 && $str[$i]==">") $start = 1;
    else if($start==1){
     if($str[$i]=="<"){ $start = 0; $alltext .= " "; }
     else if(ord($str[$i])>32) $alltext .= $str[$i];
    }
  }
  $alltext = preg_replace("/&([^;&]*)(;|&)/"," ",$alltext);
  $alltext = preg_replace("/　{1,}/"," ",$alltext);
  $alltext = preg_replace("/ {1,}/"," ",$alltext);
  return $alltext;
}