Most (newer) barcode scanner emulate a keyboard. It behaves as if you typed it in. Configure the barcode scanner to end with "end of line contant" or CR.
Then test the barcode scanner in something like NotePad. You can then create a small vi that takes a string from a string control and displays it into a string indicator. Put the String Control in a while loop and scan the length of the string control if GT 0 then stop. Run the vi and you'll see that what was scanned is displayed in both the control and the indicator. It's simple. JLV