Handling user submitted urls

[Braxton]

I am currently writing a simple blog script for my website and I have reached the point where I am writing in the commenting feature. I want to allow the author of a comment to also provide their url much like how wordpress comments work. The thing that I'm unsure about is the url. Some users like to simply type domain.com and other http://domain.com. My question is, is there a function or method of which would be good to use here to make sure that when a user submits the info, the url won't break or anything like that. I hope this makes sense.

[requinix]

URL won't break? How would it break in the first place?

[Braxton]

Let's say the user simply supplies "domain.com", Should I just check for http:// within the string and if it does not exist within, then add it? I just tested using "domain.com" and when I click on it, I am taken to "http://localhost/domain.com" I used the term "break" as I didn't know how else to say it.

[requinix]

Are you modifying existing WordPress code or writing something for yourself?

[DavidAM]

You got the "localhost/" on it because without the leading slash (on "domain.com") the browser thinks it is a relative path, and automatically applies the path of the current page. At the very least, you need a slash at the beginning: /domain.com.

 

However, I would instruct the user to include the protocol ("http:") and reject the submission if it is not present. It is possible that the user's protocol is https:, so you really want to have them enter it, rather than guess.

 

I would resist storing or showing it without the protocol, because if you show it through some other protocol (i.e. rss or some future protocol), you don't really know what that (future) reader will do to unqualified addresses.

[handlegeek]

Yes, you can use PHP to check if the URL starts with "http://" or "https://" and show error message OR prefix "http://" considering http:// to be default. In addition to that, using JavaScript you can validate the URL field - To check if it follows a valid URL pattern and show a error message to the user.