'--------------------------... 'text box class '--------------------------... Option Explicit On Option Strict On Public Class TextBox2 Inherits System.Windows.Forms.TextBox Private Sub txtBarcode_KeyUp(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyEve... Handles MyBase.KeyUp '--------------------------... 'allow control-v, control-c, control-x, control-a '--------------------------...

Original Article: http://weblogs.asp.net/rosh... Problem & Solution: Allow only one instance of any MDI child form in your MDI application One of the things I needed to do at an MDI application I was involved with was the ability to only load a specific form once, and make sure it does not load again. That form could not be modal, but could only have one instance running inside the MDI parent. I came up with a rather elegant solution, if I do say so myself :)...