Question

Let’s say I’ve got a control and I want to prevent it from being edited.

Setting the Enabled property of the control to False will work but the control appearance will change accordingly, usually to a difficult to read black over gray font. When readability is still important, this is a real problem.

For a TextBox, there are a few obvious fixes :

Textbox1.BackColor = Color.White; 

or

Textbox1.ReadOnly= true; // instead of setting Enabled to false 

but unfortunately this won’t work for every controls (eg radio buttons)

Another solution is to let the Enabled property untouched, and to subscribe to the focus event like this (but this isn’t a really elegant solution)

    this.Textbox1.Enter += new System.EventHandler(this.Textbox1_Enter);      private void Textbox1_Enter(object sender, EventArgs e)     {       Textbox1.FindForm().ActiveControl = null;     } 

Have you seen other ways of dealing with this problem? (and I mean real world solutions ; of course you can capture a screenshot of the control and display the copy over the control…:p)

Answer 1

There is an argument that interfering with standard Windows behaviour is confusing for the user, but that aside I have seen this done before, although more commonly in C++. You can subclass the control and handle paint messages yourself. When the control’s enabled just delegate the drawing to the base class. When the control’s disabled you can either let the base class draw itself and then do some custom drawing over the top or you can just draw the entire thing youself. I’d strongly recommend the first of these options.