title: WinForms - MaskedTextBox - "variable-width" masking possible?
body: <p>I need to create a WinForms textbox that allows decimal text exclusive-or integer text. Also, I don't wish to be required to specify the length of the text in the mask; the user should be able to enter as many characters as he wants, as long as the text fits the decimal or integer mold. However, the MaskedTextBox doesn't allow variable-length masking, as far as I know; I can't find a pre-existing control that does this, either.</p>
  
  <p>Advice? I suppose I could inherit TextBox, override OnKeyPress and do the work there, but I don't know whether a pre-existing control would do things more gracefully.</p>