C# code to generate Modulus 11 Check Digit

Status: Pending
Premie: $10
Mottatte bidrag: 3
Vinner: Orscorp

Winner

Konkurransesammendrag

Greetings, I am looking for a simple task. I need to determine the check digit for a 47 digit integer.
The deliverable is a simple one page site where I input the 47 digit integer and by pressing "calculate" I get the check digit.
Also, full c# code is to be delivered.

If you dont know what Modulus 11 is, please dont be part of contest.