If it is one text object, you can't make part of it visible and part invisible. But you can mask the text to show just what's inside the box, like you mask any layer. See below an example:
https://www.dropbox.com/s/qg2hgaxm9rtuo ... .capx?dl=1
The only differenece is you'll be masking a text, not an image.
Hope this helps. Cheers!
thank for u answer ,it,s usefull,