Restricting the format of an input tag

Question

Within an <input type="text" /> tag how do you I mask the input field so that the user is resricted to the following format [].[] and in between the brackets can be any number of characters.

As an example:

"[Analysis].[Analysis]" 

or a another example:

[Analysis-Result].[Analysis Result]"

Answer 1

Use this plugin http://digitalbush.com/projects/masked-input-plugin/#demo