URL field validation

I’m having trouble validating a URL field that I have created. Has anybody created any validation for this type of field that they could share?

I specifically want to check for “http://”, at least one period “.” and NO spaces. Checking for spaces, in particular, has been difficult for me to get working.

Any suggestions are much appreciated!

Are you trying to use the Regular Expression validation type? Found the following regex that validates URLs

^http\://[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}(/\S*)?$