一些奇怪：）

Delegate target =
  (target0 = target as CallTargetWithContext0) ??
  (target1 = target as CallTargetWithContext1) ??
  (target2 = target as CallTargetWithContext2) ??
  (target3 = target as CallTargetWithContext3) ??
  (target4 = target as CallTargetWithContext4) ??
  (target5 = target as CallTargetWithContext5) ??
  ((Delegate)(targetN = target as CallTargetWithContextN));

值得注意的是，出于某种原因需要最后一个演员阵容。缺陷还是设计？

可以将多个属性放在一对方括号中：

    [OperationContract, ServiceKnownType(typeof(Prism)), ServiceKnownType(typeof(Cuboid))]
    Shape GetShape();

将枚举值转换为字符串值

给定枚举

enum Country
{
    UnitedKingdom, 
    UnitedStates,
    UnitedArabEmirates,
}

使用它：

public static void PrintEnumAsString( Country country )
{
    Console.Writeline( country.ToString() );
}

将枚举值的名称打印为字符串，例如“UnitedKingdom”

首先-DebuggerTypeProxy。

[DebuggerTypeProxy(typeof(HashtableDebugView))]
class MyHashtable : Hashtable
{
    private const string TestString = 
        "This should not appear in the debug window.";

    internal class HashtableDebugView
    {
        private Hashtable hashtable;
        public const string TestStringProxy = 
            "This should appear in the debug window.";

        // The constructor for the type proxy class must have a 
        // constructor that takes the target type as a parameter.
        public HashtableDebugView(Hashtable hashtable)
        {
            this.hashtable = hashtable;
        }
    }
}

第二步：

ICustomTypeDescriptor

我不知道泛型方法有助于避免使用方法重载。下面是打印int和double数字的重载方法。

    private static void printNumbers(int [] intNumbers)
    { 
        foreach(int element in intNumbers)
        {
            Console.WriteLine(element);
        }

    }

    private static void printNumbers(double[] doubleNumbers)
    {
        foreach (double element in doubleNumbers)
        {
            Console.WriteLine(element);
        }
    }

泛型方法，有助于为上述两种方法提供一种方法

    private static void printNumbers<E>(E [] Numbers)
    {
        foreach (E element in Numbers)
        {
            Console.WriteLine(element);
        }
    }

对于数据库应用程序开发人员来说，这可能很基本，但我花了一段时间才意识到null与DBNull.value不同。

当您想查看数据库记录中的值是否为空时，必须使用DBNull.value。