$descclear = str_replace(\r,,$descclear);//过滤换行
$descclear = str_replace(\n,,$descclear);//过滤换行
$descclear = str_replace(\t,,$descclear);//过滤换行
$descclear = str_replace(\r\n,,$descclear);//过滤换行
$descclear = preg_replace(/\s+/, , $descclear);//过滤多余回车
$descclear = preg_replace(/<[ ]+/si,<,$descclear); //过滤<__(/isu;
$descclear = preg_replace($pat,,$descclear);