Adding Items to a List Box Dynamically

I have a text field, a button and a list box. When the button is clicked, the text from the text field is supposed to be added as a new item to the list box. I have tried adding the text to a HashSet and then binding the list box's items property to the HashSet, but this isn't working. Is there a better way to do this?

Thanks.

[343 byte] By [karim86] at [2007-11-26 9:35:13]