How do I make a read-only textbox that selects all text when tapped?

How do I make a read-only textbox that selects all text when tapped?

I am trying to make a textbox look like a textblock (no white background
or anything) so that I can display resulting text and numbers in it. When
the user taps on the text I want the whole result to be highlighted for
easy copy/pasting. This is for a Windows Phone 8 Application. Thanks!