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I want to do something like this : myYear = record.GetValueOrNull<int?>("myYear"), Notice the nullable type as the generic parameter. Since the GetValueOrNull function could return null my first attempt was this: public static T GetValueOrNull<T>(this DbDataRecord reader, string columnName) where T : class { object columnValue = reader[columnName]; if (!(columnValue is DBNull)) { return (T)columnValue; } return null; } But the error I'm getting now is: The type 'int?' must be a reference type in order to use it as parameter 'T' in the generic type or method Right! Nullable<int> is a struct ! So I tried changing the class constraint to a struct constraint (and as a side effect can't return null any more): public static T GetValueOrNull<T>(this DbDataRecord reader, string columnName) where T : struct Now the assignment: myYear = record.GetValueOrNull<int?>("myYear"); Gives the following error: The type 'int?' must be a non-nullable value type in order to use it as parameter 'T' in the generic type or method Is specifying a nullable type as a generic parameter at all possible?

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