ASP.Net Application Problem

[Mei Yoong]

I'm doing a web application that connects to a reader where there are some line sof code that need to be execute under the button1.click events. Under the event, there is a DO loop where it always check whether there is any bar code scanned over the reader. If there is a barcode scanned, then the bardcode ID will be display in a listbox, else the DO loop continues to loop till the user press the Stop button. Is there anywhere which the listbox in the page will display the barcode ID on runtime once the tag was scanned and continue to loop if user did not press the Stop button? Pelase help. Thanks in advance