in using the ItemInserting event of a combobox, how to I get the text that was typed in the combobox in codebehind, (vb)

When I change text in a combo box, and the text doesn't match, I am running an "ItemInserting" Script. I am trying to pull the text typed into the combobox out and then insert it with in the ItemInserting event. But when I try to grab the combobox.text value, it is the value of the index that is currently selected.
How can I get the text typed into the combobox in codebehind (vb)