Hi,
I think Abhinav's solution is good.There explains how to disable the paste command using xaml and by code dynamically.
DataObject.AddPastingHandler(ntb.textBox1, new DataObjectPastingEventHandler(OnPasteCommand));
use the event handler as
void OnPasteCommand(object sender, DataObjectPastingEventArgs e)
{
e.CancelCommand();
}
If you would like to use your approch,the problem here is the Paste command doesn't execute on Ctrl+v but it still possible to paste through the context menu of textbox.Still you would like to choose your approch you can use the code like
KeyBinding vBinding = new KeyBinding(ApplicationCommands.NotACommand,new KeyGesture(Key.V, ModifierKeys.Control));
ntb.textBox1.InputBindings.Add(vBinding);