Gets or sets the character used to represent the absence of user input in MaskedTextBox.
The character used to prompt the user for input. The default is an underscore (_).
PromptChar will be displayed in MaskedTextBox for any mask position that the user has not yet filled in.
Use the HidePromptOnLeave property to specify whether the prompt is displayed when MaskedTextBox does not have focus.
MaskedTextBox Class | Resco.Controls.MaskedTextBox Namespace