This is a masked input plugin for the jQuery javascript library. It allows a user to more easily enter fixed width input where you would like them to enter the data in a certain format (dates,phone numbers, etc). It has been tested on Internet Explorer, Firefox, Safari, Opera, and Chrome. A mask is defined by a format made up of mask literals and mask definitions. Any character not in the definitions list below is considered a mask literal. Mask literals will be automatically entered for the user as they type and will not be able to be removed by the user.The following mask definitions are predefined:

• a - Represents an alpha character (A-Z,a-z)
• 9 - Represents a numeric character (0-9)
• * - Represents an alphanumeric character (A-Z,a-z,0-9)

If your requirements aren't met by the predefined placeholders, you can always add your own. For example, maybe you need a mask to only allow hexadecimal characters. You can add your own definition for a placeholder, say 'h', like so: $.mask.definitions['h'] = "[A-Fa-f0-9]"; Then you can use that to mask for something like css colors in hex with a mask "#hhhhhh".

By design, this plugin will reject input which doesn't complete the mask. You can bypass this by using a '?' character at the position where you would like to consider input optional. For example, a mask of "(999) 999-9999? x99999" would require only the first 10 digits of a phone number with extension being optional.