C++ builder 2007, scan in edit with barcode scanner

[Leite333]

Goodmorning

I have a simple application with one edit inside. So the user in this edit use a barcode scanner and scan. I have the above code

if(Key == '\n' ||Key == '\r')

checkCustomer();

So when it scans everything is ok. but when the user put a number from keyboard or letter i want to bring a message to him to use scanner with else.

all the code is on
Edit1KeyDown event