Implement a credit card verification as a WEB application using ASP.NET. You will get the following information from the user:
The user's choice of credit card type to be specified using a drop-down list. Card number, as a text box.
Write an ASP.NET function that checks the validity of a credit card specified by the supplied parameters containing the card number and card type. The function returns true or false, depending on whether the credit card name / number combination is found to be valid. If it is not valid, a numeric code is loaded into a global variable, which may be used to index into a global array of error messages as follows.
1. "Unknown card type",
2. "No card number provided",
3. "Credit card number is in invalid format",
4. "Credit card number is invalid",
5. "Credit card number has an inappropriate number of digits" etc.
