Binding List to GridView

You must use public properties for DataBinding. Update your class as follows:

  public class CreditCard
    {
        public String A_Number { get; set; }
        public String A_Name { get; set; }
        public String A_Type { get; set; }
        public String A_Owner_Type { get; set; }
        public String Bank_City { get; set; }
        public String Bank_State { get; set; }
        public String Bank_ZIP { get; set; }
        public String Balance { get; set; }
        public String C_Username { get; set; }

        public CreditCard() { }
    }

You have defined your CreditCard as an object with fields. Data binding can only be done with properties. So, you need to do something like this for all fields:

public String A_Number { get; set; }