Enum types

An Ice enumeration maps to a public C# enumeration with the same name, and each Ice enumerator maps to the C# enumerator with the same name. For example:

enum Fruit { Apple, Pear, Orange }

enum Fruit { Apple, Pear, Orange }

Extension methods

The Ice compiler generates extension methods to encode and decode instances of each enum:

• EncodeName to encode an enum instance
• DecodeName to decode an enum instance

With our Fruit example, we get:

public static class FruitIceEncoderExtensions
{
    public static void EncodeFruit(this ref IceEncoder encoder, Fruit value) => ...
}

public static class FruitIceDecoderExtensions
{
    public static Fruit DecodeFruit(this ref IceDecoder decoder) => ...
}

The Ice compiler also generates an extension method AsName to convert an int value into an enumerator.

With our Fruit example:

public static class FruitIntExtensions
{
    public static Fruit AsFruit(this int value) => ...
}

This conversion fails and throws [InvalidDataException] when the value does not correspond to any enumerator of the Fruit enumeration.

cs:attribute metadata directive

The "cs:attribute"cs-attribute metadata directive adds the specified C# attribute to the mapped C# enum. You can use it to add the FlagsAttribute to the mapped C# enum. For example:

["cs:attribute:Flags"]
enum MultiHue
{
    None = 0,
    Black = 1,
    Red = 2,
    Green = 4,
    Blue = 8
}

[Flags]
public enum MultiHue
{
    None = 0,
    Black = 1,
    Red = 2,
    Green = 4,
    Blue = 8,
}

The Flags attribute is moderately useful with IceRPC since the decoding code only allows values that match known enumerators. For example, you won't be able to decode 6 for Red and Green since 6 doesn't correspond to any enumerator.