How do I allow selection of everything in my multiline textbox?
It seems strange to me that there would be no way to do this; there should be something framed out of the box.
In case of Windows Forms :
textbox.SelectAll();
Try the SelectAll method (actually located on the TextBoxBase).
TextBoxBase b = GetTheTextBox(); b.SelectAll();
How about textbox1.SelectAll() ?
textbox1.SelectAll()
You can also use
textbox1..Select(0, textbox1.Text.Length);
and return the HideSelection property to False .