[DotNetDevelopment] correct syntax for switch statement

[adiel]

Hello, this must be an easy one.  I want to perform code based on the
selected item from a radio button in asp.net.  I have the following
code:

                // Setup Living Area
                switch (true)
                {
                    case radRental.Checked:
                        livingArea = "Rental Properties Listing";
                        break;
                    case radHome.Checked:
                        livingArea = "Home Property Listing";
                        break;
                    case radApartment.Checked:
                        livingArea = "Apartment Property Listing";
                        break;
                    default:
                        livingArea = "";
                        break;
                }

I am getting an error stating "a constant value is expected" on each
item in the case statement.  I know I must be missing a cast or
something, can someone help?

Thanks,
Adiel