在.NET运行时知道分类信息(1) Paul_Ni（原作）

反射概述

• 使用 Assembly 定义和加载程序集，加载在程序集清单中列出的模块，以及从此程序集中查找类型并创建该类型的实例。
  
• 使用 Module 了解如下的类似信息：包含模块的程序集以及模块中的类等。您还可以获取在模块上定义的所有全局方法或其他特定的非全局方法。
  
• 使用 ConstructorInfo 了解如下的类似信息：构造函数的名称、参数、访问修饰符（如 public 或 private）和实现详细信息（如 abstract 或 virtual）等。使用 Type 对象的 GetConstructors 或 GetConstructor 方法来调用特定的构造函数。
  
• 使用 MethodInfo 来了解如下的类似信息：方法的名称、返回类型、参数、访问修饰符（如 public 或 private）和实现详细信息（如 abstract 或 virtual）等。使用 Type 对象的 GetMethods 或 GetMethod 方法来调用特定的方法。
  
• 使用 FieldInfo 来了解如下的类似信息：字段的名称、访问修饰符（如 public 或 private）和实现详细信息（如 static）等；并获取或设置字段值。
  
• 使用 EventInfo 来了解如下的类似信息：事件的名称、事件处理程序数据类型、自定义属性、声明类型和反射类型等；并添加或移除事件处理程序。
  
• 使用 PropertyInfo 来了解如下的类似信息：属性的名称、数据类型、声明类型、反射类型和只读或可写状态等；并获取或设置属性值。
  
• 使用 ParameterInfo 来了解如下的类似信息：参数的名称、数据类型、参数是输入参数还是输出参数，以及参数在方法签名中的位置等。

查看类型信息

[C#]

// Get the mscorlib assembly in which the object is defined.

Assembly a = typeof(Object).Module.Assembly;

[C#]

// Load an assembly using its file name.

Assembly a = Assembly.LoadFrom ("MyExe.exe");

// Get the type names from the assembly.

Type [] types2 = a.GetTypes ();

foreach (Type t in types2)

{

Console.WriteLine (t.FullName);

}

System.Type 和 ConstructorInfo

[C#]

// This program lists all the public constructors 

// of the System.String class.

using System;

using System.Reflection;

class ListMembers {

 public static void Main(String[] args) {

Type t = typeof(System.String);

Console.WriteLine ("Listing all the public constructors of the {0} type", t);

// Constructors 

ConstructorInfo[] ci = t.GetConstructors(BindingFlags.Public | BindingFlags.Instance);

Console.WriteLine ("//Constructors");

PrintMembers (ci);

 }

 public static void PrintMembers(MemberInfo [] ms) {

foreach (MemberInfo m in ms) {

Console.WriteLine ("{0}{1}", " ", m);

}

Console.WriteLine();

 }

}

MemberInfo、MethodInfo、FieldInfo 和 PropertyInfo

[C#]

using System;

using System.IO;

using System.Reflection;

class Mymemberinfo

{ 

public static void Main(string[] args)

{ 

 Console.WriteLine ("\nReflection.MemberInfo");

 // Get the Type and MemberInfo.

 Type MyType =Type.GetType("System.IO.File");

 MemberInfo[] Mymemberinfoarray = MyType.GetMembers(); 

 // Get and display the DeclaringType method. 

 Console.WriteLine("\nThere are {0} members in {1}.", 

Mymemberinfoarray.Length, MyType.FullName);

 Console.WriteLine("{0}.", MyType.FullName); 

 if (MyType.IsPublic)

 {

Console.WriteLine("{0} is public.", MyType.FullName);

}

 }

}

[C#]

// This code displays information about the GetValue method of FieldInfo.

using System;

using System.Reflection;

class MyMethodInfo {

 public static int Main() {

Console.WriteLine("Reflection.MethodInfo");

// Get and display the Type.

Type MyType = Type.GetType("System.Reflection.FieldInfo");

// Specify the member for which you want type information here.

MethodInfo Mymethodinfo = MyType.GetMethod("GetValue");

Console.WriteLine(MyType.FullName + "." + Mymethodinfo.Name);

// Get and display the MemberType property.

MemberTypes Mymembertypes = Mymethodinfo.MemberType;

if (MemberTypes.Constructor == Mymembertypes) {

Console.WriteLine("MemberType is of type All"); 

}

else if (MemberTypes.Custom == Mymembertypes) {

 Console.WriteLine("MemberType is of type Custom"); 

}

else if (MemberTypes.Event == Mymembertypes) {

 Console.WriteLine("MemberType is of type Event"); 

}

else if (MemberTypes.Field == Mymembertypes) {

 Console.WriteLine("MemberType is of type Field"); 

}

else if (MemberTypes.Method == Mymembertypes) {

 Console.WriteLine("MemberType is of type Method"); 

}

else if (MemberTypes.Property == Mymembertypes) {

 Console.WriteLine("MemberType is of type Property"); 

}

else if (MemberTypes.TypeInfo == Mymembertypes) {

 Console.WriteLine("MemberType is of type TypeInfo"); 

}

return 0;

 }

}

[C#]

// This program lists all the members of the 

// System.IO.BufferedStream class.

using System;

using System.IO;

using System.Reflection;

class ListMembers {

 public static void Main(String[] args) {

// Specify the class here.

Type t = typeof (System.IO.BufferedStream);

Console.WriteLine ("Listing all the members (public and non public) of the {0} type", t);

// Static Fields are listed first.

FieldInfo [] fi = t.GetFields (BindingFlags.Static | 

 BindingFlags.NonPublic | BindingFlags.Public);

Console.WriteLine ("// Static Fields");

PrintMembers (fi);

// Static Properties 

PropertyInfo [] pi = t.GetProperties (BindingFlags.Static | 

 BindingFlags.NonPublic | BindingFlags.Public);

Console.WriteLine ("// Static Properties");

PrintMembers (pi);

// Static Events 

EventInfo [] ei = t.GetEvents (BindingFlags.Static | 

 BindingFlags.NonPublic | BindingFlags.Public);

Console.WriteLine ("// Static Events");

PrintMembers (ei);

// Static Methods 

MethodInfo [] mi = t.GetMethods (BindingFlags.Static | 

 BindingFlags.NonPublic | BindingFlags.Public);

Console.WriteLine ("// Static Methods");

PrintMembers (mi);

// Constructors 

ConstructorInfo [] ci = t.GetConstructors (BindingFlags.Instance | 

 BindingFlags.NonPublic | BindingFlags.Public);

Console.WriteLine ("// Constructors");

PrintMembers (ci);

// Instance Fields 

fi = t.GetFields (BindingFlags.Instance | BindingFlags.NonPublic | 

 BindingFlags.Public);

Console.WriteLine ("// Instance Fields");

PrintMembers (fi);

// Instance Properites 

pi = t.GetProperties (BindingFlags.Instance | BindingFlags.NonPublic | 

 BindingFlags.Public);

Console.WriteLine ("// Instance Properties");

PrintMembers (pi);

// Instance Events 

ei = t.GetEvents (BindingFlags.Instance | BindingFlags.NonPublic | 

 BindingFlags.Public);

Console.WriteLine ("// Instance Events");

PrintMembers (ei);

// Instance Methods 

mi = t.GetMethods (BindingFlags.Instance | BindingFlags.NonPublic | 

 BindingFlags.Public);

Console.WriteLine ("// Instance Methods");

PrintMembers (mi);

Console.WriteLine ("\r\nPress Return to exit.");

Console.Read();

 }

 public static void PrintMembers (MemberInfo [] ms) {

foreach (MemberInfo m in ms) {

 Console.WriteLine ("{0}{1}", " ", m);

}

Console.WriteLine();

 }

}