입력값에서 쌍따옴표 처리 > PHP

// 입력
function in_slashes($str)  //slashes
{
    $rstr = trim($str);
    $rstr = str_replace ("<", "&lt;", $rstr);
    $rstr = str_replace (">", "&gt;", $rstr);   
    $rstr = str_replace("\"","&quot;",$rstr);
    $rstr = str_replace("'","&apos;",$rstr);
    $rstr = AddSlashes($rstr);
    return $rstr;
}

// 출력
function out_slashes($str,$tagYn='Y')
{
    $rstr = trim($str);
    $rstr = stripslashes($rstr);
    if($tagYn == 'N')
    {
    $rstr = str_replace ("<", "&lt;", $rstr);
    $rstr = str_replace (">", "&gt;", $rstr);   
    }
    $rstr = str_replace("\"","&quot;",$rstr);
    $rstr = str_replace("'","&apos;",$rstr);
   
    return $rstr;
}