Question

How can I override the copy/paste functions in a Richtextbox C# application.
Including ctrl-c/ctrl-v and right click copy/paste.

It’s WPF richtextBox.

Answer 1

To override the command functions:

protected override bool ProcessCmdKey(ref Message msg, Keys keyData) 
{
  if (keyData == (Keys.Control | Keys.C))
  {
    //your implementation
    return true;
  } 
  else if (keyData == (Keys.Control | Keys.V))
  {
    //your implementation
    return true;
  } 
  else 
  {
    return base.ProcessCmdKey(ref msg, keyData);
  }
}

And right-clicking is not supported in a Winforms RichTextBox

–EDIT–

Realized too late this was a WPF question. To do this in WPF you will need to attach a custom Copy and Paste handler:

DataObject.AddPastingHandler(myRichTextBox, MyPasteCommand);
DataObject.AddCopyingHandler(myRichTextBox, MyCopyCommand);

private void MyPasteCommand(object sender, DataObjectEventArgs e)
{
    //do stuff
}

private void MyCopyCommand(object sender, DataObjectEventArgs e)
{
    //do stuff
}