Regex URL javascript

Question

About validation URL format: regex using:

const regex = /^(?:(?:https?):\/\/)?(?:(?!(?:10|127)(?:\.\d{1,3}){3})(?!(?:169\.254|192\.168)(?:\.\d{1,3}){2})(?!172\.(?:1[6-9]|2\d|3[0-1])(?:\.\d{1,3}){2})(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-zA-Z0-9]-*)*[a-zA-Z0-9]+)(?:\.(?:[a-zA-Z0-9]-*)*[a-zA-Z0-9]+)*(?:\.(?:[a-zA-Z]{2,})))(?::\d{2,5})?(?:\/\S*)?$/;

should pass:

const string1 = 'http://www.example.com'

const string2 = 'http://example.com'

const string3 = 'www.example.com'

const string4 = 'example.com'

should fail: const string5 = 'www.example' const string6 = 'http://www.example'

but string5 , string6 still pass, I just newbie regex.

Link reference: https://jsbin.com/hegocoyoge/edit?js,console

That's quite a complicated regular expression, can you explain what exactly you're trying to do with it? — CertainPerformance, Dec 03 '18 at 07:32
Possible duplicate of [What is the best regular expression to check if a string is a valid URL?](https://stackoverflow.com/questions/161738/what-is-the-best-regular-expression-to-check-if-a-string-is-a-valid-url) — david, Dec 03 '18 at 07:32
I found this solution on stack then sorry I oso dont understand clearly this regex, but I wanna check 1 more option is `www.example` or `http://www.example` will fail -_- — Xuân Bình, Dec 03 '18 at 07:38

Mr.Turtle · Answer 1 · 2018-12-03T07:49:11.743

0

Your regex seems very complex. It doesn't have to be.. Try this:

var expression = /[-a-zA-Z0-9@:%_\+.~#?&//=]{2,256}\.[a-z]{2,4}\b(\/[-a-zA-Z0-9@:%_\+.~#?&//=]*)?/gi;
var regex = new RegExp(expression);
var t = 'www.google.com';
if (t.match(regex)) {
  console.log("This is a valid url");
} else {
  console.log("This is not a valid url");
}

edited Dec 03 '18 at 07:49

answered Dec 03 '18 at 07:33

Mr.Turtle

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Thanks for your support sir – Xuân Bình Dec 03 '18 at 07:55

score 0 · Accepted Answer · answered Dec 03 '18 at 07:48

0

Why don't you use this simple compact regex, instead of your so big unmaintainable regex? Which seems to satisfy your exact requirements mentioned in your post's samples.

^(http:\/\/)?(www\.)?\w+\.\w{1,3}$

Demo

answered Dec 03 '18 at 07:48

Pushpesh Kumar Rajwanshi

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Thank so much sir, it really what I want ^^ – Xuân Bình Dec 03 '18 at 07:54
@XuânBình: If my solution worked for you, can you please upvote/accept my answer? Thanks :) – Pushpesh Kumar Rajwanshi Dec 03 '18 at 08:56
oh yes, you need 15+ rep for voting privilege I guess. Keep asking good questions and give good answers so you keep getting more rep and privileges :) – Pushpesh Kumar Rajwanshi Dec 03 '18 at 09:24

score -1 · Answer 3 · answered Dec 03 '18 at 07:35

-1

I'll highly recommend use some library. For example validator. Authors already solved these problems. If you still want to implement your own (unreadable) regEx try to look to source of some isEmail library like: https://github.com/chriso/validator.js/blob/master/src/lib/isEmail.js

answered Dec 03 '18 at 07:35

Jakub Švehla

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Thanks for your suggestion, I'm using it in my project, but not enough for validate. So i need combine with regex for make sure validation is correct – Xuân Bình Dec 03 '18 at 07:39

Regex URL javascript

3 Answers3