How can I add an unremovable prefix to an HTML input field?

Question

Using jQuery, how can I add a default value of http:// into an input field that can’t be removed, but that still allows you to type a URL after it?

Defa

Answer 1

If you insist on 'http://' being the the default value, add the "value" attribute to the input tag:

Allow users to remove it if they wish, yet validate when the form is sent. (jQuery's validation plugin)