I'm using this code to place a date in a textbox2 after the user has selected the begin date for textbox1. It works fine, but I can only get it to work after the page has been postedback. Can I use some java code, so the textbox will populate as soon as the date is placed in the first textbox?

The user is selecting the date from a popup calendar which is on another page.

txtIntDisEndDate.Text = DateAdd(DateInterval.Day, 1, CDate(txtBidOpenDate.Text))