regex to check valid url either http or www

Question

I want to check that user inserted URL is valid or not. I have different cases to allow user to insert URL

1) www.test.com (valid)
2) http://test.com (valid)
3) http://www.test.com (valid)
4) www.test (not valid)

So this way user will able to insert www or http, If user insert only www then pre-append http:// before URL. I found many regex but they strictly check http://.

Thanks in advance.

"Append before" is a contradiction in terms. The word you're looking for is "prepend." — Jordan Running, Jul 30 '15 at 05:24

score 5 · Accepted Answer · answered Jul 30 '15 at 05:25

5

see this link may help you.

<?php
// Variable to check
$url = "http://www.w3schools.com";

// Validate url
if (!filter_var($url, FILTER_VALIDATE_URL) === false) {
     echo("$url is a valid URL");
} else {
     echo("$url is not a valid URL");
}
?>

answered Jul 30 '15 at 05:25

Nikunj Chotaliya

802
8
19

Any idea how well this works with the new TLDs, eg "subsite.site.ninja" could be a valid url (theoretically)? – SteJ Jul 30 '15 at 05:32
1

yes it work with subsite.site.ninja also. – Nikunj Chotaliya Jul 30 '15 at 05:34
what about pre-appending http if not exist? – Himanshu Bhardiya Jul 30 '15 at 05:40
i think you check [http://stackoverflow.com/questions/4487794/checking-if-string-contains-http] – Nikunj Chotaliya Jul 30 '15 at 05:51
@NikunjChotaliya if i type www.test.com it return fail. – Himanshu Bhardiya Jul 30 '15 at 05:52
@Sanket Sorthiya as per above comment you need to check url contains http:// or not then prepend it in url and use above php function. – Nikunj Chotaliya Jul 30 '15 at 05:53

score 0 · Answer 2 · answered Jul 30 '15 at 05:28

0

I think in point 3. you have an misstake. You have written "wwww"

apart from this, correct regex pattern could be the following:

^(https?:\/\/)?(www\.)?[a-z0-9]+\.[a-z0-9]{2,3}$

answered Jul 30 '15 at 05:28

Andret2344

653
1
12
33

There are also domains like `example.info`; `example.name`; `example.berlin` and so on which aren't considered with this regex. – take Jul 30 '15 at 05:31
so it will check if http exist or not if not exist then pre-append it. so how it will work? – Himanshu Bhardiya Jul 30 '15 at 05:39
question mark sets the previous sign or group optional, it means "http://" or "https://" can exists or not, but if exists, it cannot be different. With group `(www\.)` this same, becouse there is a question mark after it. `^` at start means that in string anything cannot be befor "http" – Andret2344 Jul 30 '15 at 06:08

regex to check valid url either http or www

2 Answers2