Nice C# constructs

Combinations in flagged enums.cs

// Kombinieren von Werten in einer flagged Enumeration
[Flags]
public enum DefaultValueHandling
{
  Include = 0,
  Ignore = 1,
  Populate = 2,
  IgnoreAndPopulate = Ignore | Populate
}

Guard Clause for null argument with Null-Coalesce and nameof.cs

// Instead
public LibraryService(IBookRepository bookRepository, IAuthorRepository authorRepository)
{
    if (bookRepository == null)
        throw new ArgumentNullException("bookRepository");

    if (authorRepository == null)
        throw new ArgumentNullException("authorRepository");

    // ...
}

// use this with nameof and Null Coalesce Operator)
public LibraryService(IBookRepository bookRepository, IAuthorRepository authorRepository)
{
    this.bookRepository = bookRepository ?? throw new ArgumentNullException(nameof(bookRepository ));
    this.authorRepository = authorRepository ?? throw new ArgumentNullException(nameof(authorRepository));
}

Switch via Type.cs

// C# 7.0
switch(shape)
{
    case Circle c:
        WriteLine($"circle with radius {c.Radius}");
        break;
    case Rectangle s when (s.Length == s.Height):
        WriteLine($"{s.Length} x {s.Height} square");
        break;
    case Rectangle r:
        WriteLine($"{r.Length} x {r.Height} rectangle");
        break;
    default:
        WriteLine("<unknown shape>");
        break;
    case null:
        throw new ArgumentNullException(nameof(shape));
}

// C# 6.0
switch(o.GetType().Name)
{
    case nameof(AType):
        break;
    case nameof(BType):
        break;
}

// C# 5.0
switch(o.GetType().Name) 
{
  case "AType":
    break;
}

// C# switch on type
// https://stackoverflow.com/questions/4478464/c-sharp-switch-on-type
// https://stackoverflow.com/questions/7252186/switch-case-on-type-c-sharp
var @switch = new Dictionary<Type, Action> {
    { typeof(Type1), () => ... },
    { typeof(Type2), () => ... },
    { typeof(Type3), () => ... },
};
@switch[typeof(MyType)]();

// How to use switch-case on a Type?
// https://stackoverflow.com/questions/7542793/how-to-use-switch-case-on-a-type
var typeProcessorMap = new Dictionary<Type, Delegate>
{
    { typeof(int), new Action<int>(i => { /* do something with i */ }) },
    { typeof(string), new Action<string>(s => { /* do something with s */ }) },
};
void ValidateProperties(object o)
{
    var t = o.GetType();
    typeProcessorMap[t].DynamicInvoke(o); // invoke appropriate delegate
}

// Switching on Types
// https://blogs.msdn.microsoft.com/jaredpar/2008/05/16/switching-on-types/
// Summary:
//   TypeSwitch is designed to prevent redundant casting and give a syntax that is similar to a normal switch/case statement.
//   For example, here is TypeSwitch in action on a standard Windows form event

Switch with Default-Exception.cs

public static DecoderType GetDecoderType(Decoder decoder)
{
    switch (decoder)
    {
        case BarcoMonitorWallDecoder _:
            return DecoderType.BarcoMonitorWall;
        ...
        default:
            throw new ArgumentOutOfRangeException(nameof(decoder), decoder, $"Could not resolve DecoderType for {decoder} with type {decoder.GetType()}");
    }
}