ComponentOne MaskedTextBox™ for Compact Framework provides a self-validating textbox. It is similar to the Microsoft MaskedTextBox control available for the Windows Forms platform.
The edit mask prevents end-users from entering invalid characters into the control and provides other enhancements of the UI. Special characters are used to specify acceptable input at each position in the control. For example, a mask for a phone number might be "(999) 000-0000", and a Social Security Number would be "000-00-0000".
The PlaceHolder property gets or sets the characters used to show spaces where the user is supposed to type. The default placeholder is "_", causing the phone number mask to appear as "(___) ___-____". Other placeholders include 0, 9, #, /, $, and so on.
The Content property gets the non-literal characters in the control. For example, in a phone number mask this would be the digits in the phone number, without spaces, parentheses, and a dash.