Input mask

In computer programming, an input mask often refers to a string expression that a developer defines, which governs what is allowed to be entered into a typical edit box. It can be said to be a template, or set format that entered data must conform to, mainly used for the purposes of data integrity by preventing transcription errors. The syntax of this string expression differs from implementation to implementation, but the fundamental input types are all supported.

Some frequent uses of input masks include inputting telephone numbers, ZIP or postcodes, times and dates.

e.g. When entering into a text box a phone number on a data capture form, in the format "(11111) 111111" the area code brackets and the space between the number and the area code will automatically be placed in.

There are many different characters for various input masks, listed on this page (as at 20/6/2006) - [http://www.microsoft.com/mspress/books/sampchap/5054c.asp