在php中阻止字符串中的url

Question

Hello i tried to prevent insert url in string like this:

function containsURL($string) {
    //check if string contains url
    $remove = array(" ", "!", ",", "@", "#", "$", "%", "^", "&", "*", "(", ")");
    $string = str_replace($remove, "", $string);
    $regex = "((https?|ftp)\:\/\/)?"; // SCHEME 
    $regex .= "([a-z0-9+!*(),;?&=\$_.-]+(\:[a-z0-9+!*(),;?&=\$_.-]+)?@)?"; // User and Pass 
    $regex .= "([a-z0-9-.]*)\.([a-z]{2,3})"; // Host or IP 
    $regex .= "(\:[0-9]{2,5})?"; // Port 
    $regex .= "(\/([a-z0-9+\$_-]\.?)+)*\/?"; // Path 
    $regex .= "(\?[a-z+&\$_.-][a-z0-9;:@&%=+\/\$_.-]*)?"; // GET Query 
    $regex .= "(#[a-z_.-][a-z0-9+\$_.-]*)?"; // Anchor 

   if(preg_match("/^{$regex}$/", $string)) //contains
        return true;
   return false;
}

but its not prevent everything urls like this:

bit.ly/18SuUzJ (with http)

its not prevent or like this

bit.ly/18SuUzJ (without http)

or other url shorter generators...

but i need to do? tnx

Answer 1

Your final regex looks like ^((https?|ftp)\:\/\/)?([a-z0-9+!*(),;?&=$_.-]+(\:[a-z0-9+!*(),;?&=$_.-]+)?@)?([a-z0-9-.]*)\.([a-z]{2,3})(\:[0-9]{2,5})?(\/([a-z0-9+$_-]\.?)+)*\/?(\?[a-z+&$_.-][a-z0-9;:@&%=+\/$_.-]*)?(#[a-z_.-][a-z0-9+$_.-]*)?$ and it does not match shortened URLs because you only defined lowercase ASCII letters in different regex parts.

If you want to match them the shortened URLs, add the case insensitive /i modifier:

if(preg_match("/^{$regex}$/i", $string))
                           ^