is URL valid or not [duplicate]

Question

Possible Duplicate:
what is the best way to check if a Url exists in PHP ?`

I'm looking for a function that returns TRUE or FALSE in php, either the URL is valid or not.

isValidURL($url); I think that simple... That would take into count all kind of URL possible.

By valid I want it to refer to an existing page of the web or other kind of files. It just should exist.

Knott

And valid means what? Syntactically valid? Or references an existing resource? – Cheongsam

@Gordon: That depends on James’ definition of validity. – Cheongsam

hey guys thanks a lot for your help. By valid i want It to referes to an existing page of the web or other kind of files. It just should exist... – Knott

possible duplicates of stackoverflow.com/search?q=check+if+url+exists+php – Conclude

A valid url is defined by its RFC faqs.org/rfcs/rfc1738.html – Torment

thanks everyone, sorry for the trouble. you still helped me a lot – Knott

This many or may not be a duplicate, but it is not a duplicate of the question that it is linked to as a duplicate. This question is asking about "valid" URLs, that question is asking about "available" URLS. Entirely possible that a valid URL is not available. – Repair

Answer 1

<?php

$url = "http://stack*overflow.org";


if(filter_var($url, FILTER_VALIDATE_URL) === FALSE)
{
        echo "Not valid";
}else{
        echo "VALID";
}
?>

this does not check tlds though

Arliearliene

this is good one, but your own example is validates to true ;) http://stackoverflow.invalid. So it's not reliable too ;-) – Hypno

@Nemoden: I know it isn't. But I told that already in my post... – Arliearliene

@Nemoden: What's wrong with the URL stackoverflow.invalid? You can setup your own local DNS to handle all sorts of TLD's. I have *.lan pointing to several local development sites behind a firewall. ;) – Tenaille

Note: this will also allow http://stackoverflow with no extension at all. – Carlita

stackoverflow is also a valid url, extentions are not required for valid urls, localhost is a valid url too – Idocrase

I guess it's a good idea to use this first and than do more reliable but slower check using get_headers(). – Crummy

Note: neither http://åäö.se or even http://example.com?s=åäö is considered valid by this method. – Natashianatassia

IPv6 addresses are also considered invalid by this method. – Nalchik

@JonasÄppelgran - Neither http://åäö.se nor http://example.com?s=åäö are valid URL, though browsers display those characters.Technically, the browser uses punycode to encode domain names and url-encodes parameters. So the correct URLs are http://xn--4cab6c.se/ and http://example.com/?s=%C3%A5%C3%A4%C3%B6 – Ditch

Answer 2

You can check whether URL is valid or not using parse_url function which would return false if URL is not valid and an array otherwise.

function isValidURL($url) { return (bool)parse_url($url); }

pretty easy way, huh? :)

Hypno

It isn't reliable:sandbox.phpcode.eu/g/a4192.php – Arliearliene

Then preg_match('|^http(s)?://[a-z0-9-]+(.[a-z0-9-]+)*(:[0-9]+)?(/.*)?$|i', $url); isn't reliable too. But I have my own reason to don't care about domain zone: they will register more domain zones tommorow and I will have to add all of them in all my projects manually? To check if URL is REALLY exists I will use cURL or sockets. For quick check this functions is enough for me. I just propose it to the OP and I don't mind if he will not mark my answer as accepted. I just offer an approach which I use myself. And it's more clean rather than regex that's why I like it ;-) – Hypno

not reliable? schema is good, you should check if it exists the name with gethostbyname: function isValidURL($url) { $parts = parse_url($url); if((bool)$parts) { return ($parts['host'] != gethostbyname($parts['host']);} else return false; } – Philippa

The docs explicitly say "This function is not meant to validate the given URL"... – Misfortune

@Kloar, "is not meant" does not mean "it can not". – Hypno

yeah, +1 it doesn't really work... – Biannulate

@Hypno it also can not though, there are absolutely tons of ways to get invalid urls through parse_url – Yell