An enumeration is a special type in the .NET Framework that is comprised of a number of named constants. While you might not have created an enumeration type yourself, you have likely used enumerations many times in day-to-day programming. For example, the rows in a GridView have a RowType property that returns an enumeration of type DataControlRowType that indicates the row's type: Header, Footer, DataRow, and so on.
When working with an enumeration we may need to display a descriptive message based on the enumeration's value. For example, using ASP.NET's Membership system you can programmatically create a new user account calling the Membership class's CreateUser method. This method specifies the success or failure of the operation via the MembershipCreateStatus enumeration. This enumeration has members like Success, InvalidUserName, InvalidPassword, DuplicateUserName, and the like. When calling this method from an ASP.NET page you might want to show the user a descriptive message based on this enumeration value.
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