I'm looking to do what should be a simple thing, but this not being my profession need some direction.

When entering a form I want 1 of the fields to be partially hidden, I want to show the last 4 characters. I also want to lock that field and 2 others from being edited. Upon clicking a button and entering a password I want to show the whole field and unlock all 3 fields and allow editing.

Any help would be appreciated. Know that I have limited to no xbasic skills.