学习c#语言的一本好书可以帮助初学者

				using System;
				using System.Reflection;
				using System.IO;
				delegate Object TwoInt32s(Int32 n1,Int32 n2);
				delegate Object OneString(String s1);
				namespace TestDelegate2
				{
					/// 
					/// Class1 的摘要说明。
					/// 
					class App
					{
						/// 
						/// 用于委托定义及封装方法为变量时(高级)
						/// 
						[STAThread]
						static void Main(string[] args)
						{
							if(args.Length							{
								String fileName=Path.GetFileNameWithoutExtension(Assembly.GetEntryAssembly().CodeBase);
								Console.WriteLine("Usage");
								Console.WriteLine("{0} delType mehtodName [Param1] [Param2]",fileName);
								Console.WriteLine(" where delType must be TwoInt32 or OneString");
								Console.WriteLine(" if delType is TwoInt32,"+
									"methodName ust be  Add or Subtract");
								Console.WriteLine(" if delType is OneString,"+
									"methodName ust be  NumChars or Reverse");
								Console.WriteLine("");
								Console.WriteLine("Examples:");
								Console.WriteLine(" {0} TwoInt32s Add 123 321",fileName);
								Console.WriteLine(" {0} TwoInt32s Subtract 123 321",fileName);
								Console.WriteLine(" {0} OneString NumChars \"Hello there\"",fileName);
								Console.WriteLine(" {0} OneString Reverse \"Hello there\"",fileName);
								return;
							}
							Type delType=Type.GetType(args[0]);//关键(得委托定义的类型)
							if(delType==null)
							{
								Console.WriteLine(" Invalid delType argument:",args[0]);
								return;
							}
							Delegate d;
							try
							{
								d=Delegate.CreateDelegate(delType,typeof(App),args[1]);//1-委托定义(变量) 2-静态方法的类名 3-封装的方法(变量)
							}
							catch(ArgumentException)
							{
								Console.WriteLine(" Invalid method argument:",args[0]);
								return;
							}
							Object[] callbackArgs=new Object[args.Length-2];
							if(d.GetType()==typeof(TwoInt32s))
							{
								try
								{
									for(Int32 a=2;a										callbackArgs[a-2]=Int32.Parse(args[a]);
								}
								catch(FormatException)
								{
									Console.WriteLine("Parameters must be integers.");
									return;
								}
							}
							if(d.GetType()==typeof(OneString))
							{
								//在指定索引的源数组与目标数据之间复制
								Array.Copy(args,2,callbackArgs,0,callbackArgs.Length);
							}
							try
							{
								Object result=d.DynamicInvoke(callbackArgs);//动态调用封装的方法
								Console.WriteLine("Result = "+result);
							}
							catch(TargetParameterCountException)
							{
								Console.WriteLine("Incorrect number of parameters specified.");
							}
						}
						static Object Add(Int32 n1,Int32 n2)
						{
							return n1+n2;
						}
						static Object Subtract(Int32 n1,Int32 n2)
						{
							return n1-n2;
						}
						static Object NumChars(String s1)
						{
							return s1.Length;
						}
						static Object Reverse(String s1)
						{
							Char[]chars=s1.ToCharArray();
							Array.Reverse(chars);
							return new String(chars);
						}
					}
				}
				
				测试数据
				
				TwoInt32s Add 123 321
				
				TwoInt32s Subtract 123 321
				
				OneString NumChars "Hello there"
				
				OneString Reverse "Hello there"