PHP去掉所有HTML代码

function replaceHtmlAndJs($document)
{
 $document = trim($document);
 if (strlen($document) <= 0)
 {
    return $document;
 }
 $search = array ("'<script[^>]*?>.*?</script>'si",  // 去掉 javascript
                  "'<[\/\!]*?[^<>]*?>'si",          // 去掉 HTML 标记
                  "'([\r\n])[\s]+'",                // 去掉空白字符
                  "'&(quot|#34);'i",                // 替换 HTML 实体
                  "'&(amp|#38);'i",
                  "'&(lt|#60);'i",
                  "'&(gt|#62);'i",
                  "'&(nbsp|#160);'i",
      "\"",
      "\'",
                  );                    // 作为 PHP 代码运行
 $replace = array ("",
                   "",
                   "\\1",
                   "\"",
                   "&",
                   "<",
                   ">",
                   " ",
       " ",
       " "
                   );
 return @preg_replace ($search, $replace, $document);
}