Can enums return string instead of an integer?

I want my enums to return string values. Not the Enum Description, they must be returning a string value, instead of an int. The code sample below is exactly what in my mind, but obviously doesn't compile.

public enum TransactionType
{
    CreditCard = "C",
    DebitCard = "D",
    CreditCardAuthenticationWithAuthorization = "CA",
    DebitCardAuthenticationWithAuthorization = "DA"
}

Any ideas?