how to disable copy, Paste and delete features on a textbox using C#

Solution 1:

In WinForms, the easiest way to disable cut, copy and paste features on a textbox is to set the ShortcutsEnabled property to false.

Solution 2:

You'd have to subclass the textbox and then override the WndProc method to intercept the windows messages before the control does.

Here's an example that illustrates a TextBox that intercepts the WM_PASTE message.

And for reference, here's the definition of the message constants:

• WM_PASTE
• WM_COPY
• WM_CUT

You'd simply ignore the inbound message, like so:

protected override void WndProc(ref Message m)
{
   if (m.Msg == WM_PASTE || m.Msg == WM_COPY || m.Msg == WM_CUT)
   {
      // ignore input if it was from a keyboard shortcut
      // or a Menu command
   }
   else
   {
      // handle the windows message normally
      base.WndProc(ref m);
   }
}

Solution 3:

Suppose you have a TextBox named textbox1. It sounds like you want to disable the cut, copy and paste functionality of a TextBox.

Try this quick and dirty proof of concept snippet:

private void Form1_Load(object sender, EventArgs e)
{
    ContextMenu _blankContextMenu = new ContextMenu();
    textBox1.ContextMenu = _blankContextMenu; 
}


private const Keys CopyKeys = Keys.Control | Keys.C;
private const Keys PasteKeys = Keys.Control | Keys.V;

protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
    if ((keyData == CopyKeys) || (keyData == PasteKeys))
    {
        return true;
    }
    else
    {
        return base.ProcessCmdKey(ref msg, keyData);
    }
} 

Solution 4:

To prevent users to copy/paste using the keyboard set ShortcutsEnabled property to false. To prevent users to copy/paste from the context menu set ContextMenu property to new ContextMenu().

if (copyPasteEnabled) {
   textBox1.ShortcutsEnabled = true;
   textBox1.ContextMenu = null;
} else {
   textBox1.ShortcutsEnabled = false;
   textBox1.ContextMenu = new ContextMenu();
}