The MaskInputRejectedEventArgs class provides information about the invalid input character, namely its zero-based position in the formatted string and a general description about why the character was rejected.
The following code example demonstrates the use of this type. In the example, an event handler reports on the occurrence of the MaskInputRejected event. This report helps you to learn when the event occurs and can assist you in debugging. To report on multiple events or on events that occur frequently, consider replacing Show with Console.WriteLine or appending the message to a multiline TextBox.
To run the example code, paste it into a project that contains an instance of type MaskedTextBox named MaskedTextBox1. Then ensure that the event handler is associated with the MaskInputRejected event.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)