Ok so lets say a listbox has

Code:
________________________
|Hi                                  |
|Bye                                |
|                                     |
|                                     |
|                                     |
|                                     |
----------------------------
How would I make it so that when my command button is clicked the textbox (text1) gets hi, and another command button is clicked, and another textbox(text2) gets bye, and so on?