Question

I have an enum defined as follows:

public enum CrystalTypeEnum { Red, White, Blue, Green };

and I have a static function that returns the string representation of a given enum value:

public static string toString(CrystalTypeEnum type)
{
    switch (type)
    {
        case CrystalTypeEnum.Red:
            return "Red";
        case CrystalTypeEnum.White:
            return "White";
        case CrystalTypeEnum.Blue:
            return "Blue";
        case CrystalTypeEnum.Green:
            return "Green";
    }
}

When I compile my code I get the following error:

CrystalType.toString(CrystalType.CrystalTypeEnum): not all code paths return a value

Why am I getting this error when clearly my switch statement covers all four cases (Red, White, Blue, Green).

Answer 1

If there is no default: control is transferred to outside of the switch statement (for values not handled by a case). This means if you don’t have a default: then you need a return statement after the switch that returns a value of the type defined by the return type of the method.