C# switch expressions

A lot of the examples of switch expressions you can find are where a function directly maps to an expression. For example:

	public static Orientation ToOrientation(Direction direction) => direction switch
	{
	Direction.Up => Orientation.North,
	Direction.Right => Orientation.East,
	Direction.Down => Orientation.South,
	Direction.Left => Orientation.West,
	_ => throw new ArgumentOutOfRangeException(nameof(direction), $"Not expected direction value: {direction}"),
	};

view raw ToOrientation.cs hosted with ❤ by GitHub

This could make you think that you cannot use a switch expression inside a method body. It certainly is possible. The only important thing is that you assign the result of your switch expression to a variable. Let’s rewrite the example above:

	public static Orientation ToOrientation(Direction direction)
	{
	var orientation=direction switch
	{
	Direction.Up => Orientation.North,
	Direction.Right => Orientation.East,
	Direction.Down => Orientation.South,
	Direction.Left => Orientation.West,
	_ => throw new ArgumentOutOfRangeException(nameof(direction), $"Not expected direction value: {direction}"),
	};
	return orientation;
	}

view raw ToOrientation2.cs hosted with ❤ by GitHub