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  • 步步为营-31-反射基础

    说明 :简单练习反射的基础包括获取dll中的数据,方法等

    程序集之间互相调用可以通过:a添加引用,b引入命名空间,来实现.但是只能调用public修辞的方法和属性.另外还可通过程序集调用

    1 创建一个控制台应用程序

    2 创建一个类库,用于生成dll,注意修改属性,使其生成的路径为控制台应用程序bin/debug目录(方便修改)

    3 获取程序集数据

     加载程序集,获取程序集数据

     3.1 加载程序集--Assembly.LoadFile(path);

      
     public static  Assembly  LoadAssembly() 
            {
                //01 注意是绝对路径
                string path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory,"Common.dll");
                //02 加载程序集
                return Assembly.LoadFile(path);
            }
    加载程序集

     3.2 获取数据

      3.2.1 方法A获得程序集所有数据类型 ass.GetTypes()

      3.2.2 方法B获得程序集所有--public数据类型 ass.GetExportedTypes()

      3.2.3 方法C根据数据名称获得指定数据,可以是私有的 ass.GetType("Common.Teacher")

      
    #region 02-获取数据(abc三种常见的方法)
    
            /// <summary>
            /// 方法A获得程序集所有数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] A_GetTypes(Assembly ass)
            {
                Type[] types = ass.GetTypes();
                return types;
            }
            /// <summary>
            /// 方法B获得程序集所有--public数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] B_GetExportedTypes(Assembly ass)
            {
                Type[] types = ass.GetExportedTypes();
                return types;
            }
            /// <summary>
            /// 方法C根据数据名称获得指定数据,可以是私有的
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
    
            private static Type[]  C_GetType(Assembly ass)
            {
                Type  atype = ass.GetType("Common.Teacher");
                Type[] types = { atype };
                return types;
            }
            #endregion
    获取数据


    小结代码+运行效果

    using System;
    using System.Collections.Generic;
    using System.IO;
    using System.Linq;
    using System.Reflection;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace 反射_基础
    {
        class Program
        {
            static void Main(string[] args)
            {
               Assembly ass = LoadAssembly();
               if (ass!=null)
               {
                   Console.WriteLine("获得所有数据");
                  Type[] typesA =  A_GetTypes(ass);
                  ShowItem(typesA);
                  Console.WriteLine();
    
                  Console.WriteLine("获得所有public数据");
                  Type[] typesB = B_GetExportedTypes(ass);
                  ShowItem(typesB);
                  Console.WriteLine();
    
                  Console.WriteLine("获得指定数据,可以是私有的");
                  Type[] typeC = C_GetType(ass);
                  ShowItem(typeC);
               }
                Console.Read();
            }
    
           
    
            #region 01加载程序集
            public static  Assembly  LoadAssembly() 
            {
                //01 注意是绝对路径
                string path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory,"Common.dll");
                //02 加载程序集
                return Assembly.LoadFile(path);
            }
            #endregion
    
            #region 02-获取数据(abc三种常见的方法)
    
            /// <summary>
            /// 方法A获得程序集所有数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] A_GetTypes(Assembly ass)
            {
                Type[] types = ass.GetTypes();
                return types;
            }
            /// <summary>
            /// 方法B获得程序集所有--public数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] B_GetExportedTypes(Assembly ass)
            {
                Type[] types = ass.GetExportedTypes();
                return types;
            }
            /// <summary>
            /// 方法C根据数据名称获得指定数据,可以是私有的
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
    
            private static Type[]  C_GetType(Assembly ass)
            {
                Type  atype = ass.GetType("Common.Teacher");
                Type[] types = { atype };
                return types;
            }
            #endregion
    
            #region 03-显示数据
            private static void ShowItem(Type[] types) 
            {
                foreach (var item in types)
                {
                    Console.WriteLine(item.Name);
                }
            }
            #endregion
        }
    }
    View Code

    4 创建对象

            4.1 CreateInstance,注意是通过无参构造函数创建的.
            4.2 Activator.CreateInstance创建对象

      
     #region 04创建对象(两种方法)
            /// <summary>
            /// 创建对象方法A,CreateInstance,注意是通过无参构造函数创建的.
            /// 方法B ,Activator.CreateInstance创建对象
            /// </summary>
            /// <param name="ass"></param>
            /// <returns></returns>
             private static object A_CreateInstance(Assembly ass)
            {
                //object obj = ass.CreateInstance("Common.Student");//如果不含有 无参构造函数,会报错
                object obj = ass.CreateInstance("Common.Teacher");
                return obj;
            }
    
            /// <summary>
             /// 方法B ,Activator.CreateInstance创建对象
            /// </summary>
            /// <param name="ass"></param>
            /// <returns></returns>
             private static object B_CreateInstance(Assembly ass)
             {
                 
                 //1获取创建对象的类型
                Type type  = ass.GetType("Common.Student");
                 object obj = Activator.CreateInstance(type,"张三",22);
                 return obj;
             }
            #endregion
    CreateInstance

    5 获取创建对象的属性,方法等
      5.1.1GetMethods

      5.1.2GetMethod

      5.2.1GetProperties

      5.2.2GetProperty

      
     #region 05获得创建对象的方法和属性
             public static MethodInfo[] A_GetMethods(object obj) 
             {
                 MethodInfo[] mes = obj.GetType().GetMethods();
                 return mes;
             }
    
             public static MethodInfo[] B_GetMethod(object obj,string methodName)
             {
                 MethodInfo me = obj.GetType().GetMethod(methodName);
                 MethodInfo[] mes ={me};
                 return mes;
             }
    
             public static  PropertyInfo[] A_GetProperties(object obj)
             {
                 PropertyInfo [] prs = obj.GetType().GetProperties();
                 return prs;
             }
    
             public static PropertyInfo[] B_GetProperty(object obj, string proName)
             {
                 PropertyInfo pr = obj.GetType().GetProperty(proName);
                 PropertyInfo[] prs = { pr };
                 return prs;
             }
    
            #endregion
    05获得创建对象的方法和属性

       5.3 调用创建对象的SayHello方法
                   me[0].Invoke(objB, null);

       5.4 获得Age属性的值
                  pro[0].SetValue(objB,55);               
                  Console.WriteLine(pro[0].GetValue(objB));

    代码小结:

    using System;
    using System.Collections.Generic;
    using System.IO;
    using System.Linq;
    using System.Reflection;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace 反射_基础
    {
        class Program
        {
            static void Main(string[] args)
            {
               Assembly ass = LoadAssembly();
               if (ass!=null)
               {
                   Console.WriteLine("获得所有数据");
                  Type[] typesA =  A_GetTypes(ass);
                  ShowItem(typesA);
                  Console.WriteLine();
    
                  Console.WriteLine("获得所有public数据");
                  Type[] typesB = B_GetExportedTypes(ass);
                  ShowItem(typesB);
                  Console.WriteLine();
    
                  Console.WriteLine("获得指定数据,可以是私有的");
                  Type[] typeC = C_GetType(ass);
                  ShowItem(typeC);
    
                   //创建对象
                  Console.WriteLine();
                  Console.WriteLine("方法A创建对象(必须含有无参构造函数)");
                  object objA = A_CreateInstance(ass);
                  Console.WriteLine(objA.GetType().Name);
                  Console.WriteLine();
    
                  Console.WriteLine("方法B创建对象");
                  object objB = B_CreateInstance(ass);
                  Console.WriteLine(objB.GetType().Name);
                  Console.WriteLine();
    
                   //获得创建对象那个的方法和属性
                   Console.WriteLine("创建对象的方法 们");
                   MethodInfo[] mes= A_GetMethods(objB);
                   ShowMethods(mes);
                   Console.WriteLine();
    
                   Console.WriteLine("创建对象的方法 ");              
                   MethodInfo[] me = B_GetMethod(objB,"SayHello");
                   ShowMethods(me);
                   Console.WriteLine();
    
                   Console.WriteLine("创建对象的属性 们");
                   PropertyInfo[] pros = A_GetProperties(objB);
                   ShowProperties(pros);
                   Console.WriteLine();
    
                   Console.WriteLine("创建对象的属性");
                   PropertyInfo[] pro = B_GetProperty(objB,"Age");
                   ShowProperties(pro);
                   Console.WriteLine();
    
                   //调用方法的值
                   Console.WriteLine("调用创建对象的SayHello方法");
                   me[0].Invoke(objB, null);
                   Console.WriteLine();
    
                   //获得Age属性的值
                   Console.WriteLine("获得Age属性的值");
                   pro[0].SetValue(objB,55);               
                   Console.WriteLine(pro[0].GetValue(objB));
                   
               }
                Console.Read();
            }
    
           
    
            #region 01加载程序集
            public static  Assembly  LoadAssembly() 
            {
                //01 注意是绝对路径
                string path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory,"Common.dll");
                //02 加载程序集
                return Assembly.LoadFile(path);
            }
            #endregion
    
            #region 02-获取数据(abc三种常见的方法)
    
            /// <summary>
            /// 方法A获得程序集所有数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] A_GetTypes(Assembly ass)
            {
                Type[] types = ass.GetTypes();
                return types;
            }
            /// <summary>
            /// 方法B获得程序集所有--public数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] B_GetExportedTypes(Assembly ass)
            {
                Type[] types = ass.GetExportedTypes();
                return types;
            }
            /// <summary>
            /// 方法C根据数据名称获得指定数据,可以是私有的
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
    
            private static Type[]  C_GetType(Assembly ass)
            {
                Type  atype = ass.GetType("Common.Teacher");
                Type[] types = { atype };
                return types;
            }
            #endregion
    
            #region 03-显示数据
            private static void ShowItem(Type[] types) 
            {
                foreach (var item in types)
                {
                    Console.WriteLine(item.Name);
                }
            }
            #endregion
    
            #region 04创建对象(两种方法)
            /// <summary>
            /// 创建对象方法A,CreateInstance,注意是通过无参构造函数创建的.
            /// 方法B ,Activator.CreateInstance创建对象
            /// </summary>
            /// <param name="ass"></param>
            /// <returns></returns>
             private static object A_CreateInstance(Assembly ass)
            {
                //object obj = ass.CreateInstance("Common.Student");//如果不含有 无参构造函数,会报错
                object obj = ass.CreateInstance("Common.Teacher");
                return obj;
            }
    
            /// <summary>
             /// 方法B ,Activator.CreateInstance创建对象
            /// </summary>
            /// <param name="ass"></param>
            /// <returns></returns>
             private static object B_CreateInstance(Assembly ass)
             {
                 
                 //1获取创建对象的类型
                Type type  = ass.GetType("Common.Student");
                 object obj = Activator.CreateInstance(type,"张三",22);
                 return obj;
             }
            #endregion
    
            #region 05获得创建对象的方法和属性
             public static MethodInfo[] A_GetMethods(object obj) 
             {
                 MethodInfo[] mes = obj.GetType().GetMethods();
                 return mes;
             }
    
             public static MethodInfo[] B_GetMethod(object obj,string methodName)
             {
                 MethodInfo me = obj.GetType().GetMethod(methodName);
                 MethodInfo[] mes ={me};
                 return mes;
             }
    
             public static  PropertyInfo[] A_GetProperties(object obj)
             {
                 PropertyInfo [] prs = obj.GetType().GetProperties();
                 return prs;
             }
    
             public static PropertyInfo[] B_GetProperty(object obj, string proName)
             {
                 PropertyInfo pr = obj.GetType().GetProperty(proName);
                 PropertyInfo[] prs = { pr };
                 return prs;
             }
    
            #endregion
    
            #region 06获得属性方法
             public static void ShowMethods(MethodInfo[] mes) 
             {
                 foreach (MethodInfo item in mes)
                 {
                     Console.WriteLine(item.Name);
                 }
             }
    
             public static void ShowProperties(PropertyInfo[] pros)
             {
                 foreach (PropertyInfo item in pros)
                 {
                     Console.WriteLine(item.Name);
                 }
             }
            #endregion
        }
    }
    View Code

    仔细观察获得的方法值有SayHello公共的,没有SayHi私有的方法.而且GetMethod也无法调用私有的方法

    6 反射中常用的方法  

     if (ass!=null)
               {
                 
                    Type[] types = A_GetTypes(ass);
                   //此时数组中依次存在 Brid,Person,Student,Teacher四个元素
    
                    //Studnet能否 里氏转换 为Person  子类赋值给父类
                    bool a = types[1].IsAssignableFrom(types[2]);//true
                    Console.WriteLine(a);
                    //Student是否是Person的实例
                    Type type = ass.GetType("Common.Student");
                    object obj = Activator.CreateInstance(type, "张三", 22);
                    bool b = types[1].IsInstanceOfType(obj);//true    
              
                    bool d = types[0].IsInstanceOfType(obj);//false              
                    Console.WriteLine(b);
                    Console.WriteLine(d);
    
                    //Teacher是否是Person的子类---没有接口
                    bool c = types[3].IsSubclassOf(types[1]);//true
                    Console.WriteLine(c);
    
                   //Person是否是抽象函数
                    bool e = types[1].IsAbstract;
                    Console.WriteLine(e);
               }
    常用方法

    运行效果

    总体代码:

    using System;
    using System.Collections.Generic;
    using System.IO;
    using System.Linq;
    using System.Reflection;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace 反射_基础
    {
        class Program
        {
            static void Main(string[] args)
            {
               Assembly ass = LoadAssembly();
               #region 获取程序集的数据
               if (ass == null)
               {
                   Console.WriteLine("获得所有数据");
                   Type[] typesA = A_GetTypes(ass);
                   ShowItem(typesA);
                   Console.WriteLine();
    
                   Console.WriteLine("获得所有public数据");
                   Type[] typesB = B_GetExportedTypes(ass);
                   ShowItem(typesB);
                   Console.WriteLine();
    
                   Console.WriteLine("获得指定数据,可以是私有的");
                   Type[] typeC = C_GetType(ass);
                   ShowItem(typeC);
    
                   //创建对象
                   Console.WriteLine();
                   Console.WriteLine("方法A创建对象(必须含有无参构造函数)");
                   object objA = A_CreateInstance(ass);
                   Console.WriteLine(objA.GetType().Name);
                   Console.WriteLine();
    
                   Console.WriteLine("方法B创建对象");
                   object objB = B_CreateInstance(ass);
                   Console.WriteLine(objB.GetType().Name);
                   Console.WriteLine();
    
                   //获得创建对象那个的方法和属性
                   Console.WriteLine("创建对象的方法 们");
                   MethodInfo[] mes = A_GetMethods(objB);
                   ShowMethods(mes);
                   Console.WriteLine();
    
                   Console.WriteLine("创建对象的方法 ");
                   MethodInfo[] me = B_GetMethod(objB, "SayHello");
                   ShowMethods(me);
                   Console.WriteLine();
    
                   Console.WriteLine("创建对象的属性 们");
                   PropertyInfo[] pros = A_GetProperties(objB);
                   ShowProperties(pros);
                   Console.WriteLine();
    
                   Console.WriteLine("创建对象的属性");
                   PropertyInfo[] pro = B_GetProperty(objB, "Age");
                   ShowProperties(pro);
                   Console.WriteLine();
    
                   //调用方法的值
                   Console.WriteLine("调用创建对象的SayHello方法");
                   me[0].Invoke(objB, null);
                   Console.WriteLine();
    
                   //获得Age属性的值
                   Console.WriteLine("获得Age属性的值");
                   pro[0].SetValue(objB, 55);
                   Console.WriteLine(pro[0].GetValue(objB));
    
               } 
               #endregion
    
                //bool
               if (ass!=null)
               {
                 
                    Type[] types = A_GetTypes(ass);
                   //此时数组中依次存在 Brid,Person,Student,Teacher四个元素
    
                    //Studnet能否 里氏转换 为Person  子类赋值给父类
                    bool a = types[1].IsAssignableFrom(types[2]);//true
                    Console.WriteLine(a);
                    //Student是否是Person的实例
                    Type type = ass.GetType("Common.Student");
                    object obj = Activator.CreateInstance(type, "张三", 22);
                    bool b = types[1].IsInstanceOfType(obj);//true    
              
                    bool d = types[0].IsInstanceOfType(obj);//false              
                    Console.WriteLine(b);
                    Console.WriteLine(d);
    
                    //Teacher是否是Person的子类---没有接口
                    bool c = types[3].IsSubclassOf(types[1]);//true
                    Console.WriteLine(c);
    
                   //Person是否是抽象函数
                    bool e = types[1].IsAbstract;
                    Console.WriteLine(e);
               }
             
                Console.Read();
            }
    
           
    
            #region 01加载程序集
            public static  Assembly  LoadAssembly() 
            {
                //01 注意是绝对路径
                string path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory,"Common.dll");
                //02 加载程序集
                return Assembly.LoadFile(path);
            }
            #endregion
    
            #region 02-获取数据(abc三种常见的方法)
    
            /// <summary>
            /// 方法A获得程序集所有数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] A_GetTypes(Assembly ass)
            {
                Type[] types = ass.GetTypes();
                return types;
            }
            /// <summary>
            /// 方法B获得程序集所有--public数据类型
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
            private static Type[] B_GetExportedTypes(Assembly ass)
            {
                Type[] types = ass.GetExportedTypes();
                return types;
            }
            /// <summary>
            /// 方法C根据数据名称获得指定数据,可以是私有的
            /// </summary>
            /// <param name="ass">程序集名称</param>
            /// <returns></returns>
    
            private static Type[]  C_GetType(Assembly ass)
            {
                Type  atype = ass.GetType("Common.Teacher");
                Type[] types = { atype };
                return types;
            }
            #endregion
    
            #region 03-显示数据
            private static void ShowItem(Type[] types) 
            {
                foreach (var item in types)
                {
                    Console.WriteLine(item.Name);
                }
            }
            #endregion
    
            #region 04创建对象(两种方法)
            /// <summary>
            /// 创建对象方法A,CreateInstance,注意是通过无参构造函数创建的.
            /// 方法B ,Activator.CreateInstance创建对象
            /// </summary>
            /// <param name="ass"></param>
            /// <returns></returns>
             private static object A_CreateInstance(Assembly ass)
            {
                //object obj = ass.CreateInstance("Common.Student");//如果不含有 无参构造函数,会报错
                object obj = ass.CreateInstance("Common.Teacher");
                return obj;
            }
    
            /// <summary>
             /// 方法B ,Activator.CreateInstance创建对象
            /// </summary>
            /// <param name="ass"></param>
            /// <returns></returns>
             private static object B_CreateInstance(Assembly ass)
             {
                 
                 //1获取创建对象的类型
                Type type  = ass.GetType("Common.Student");
                 object obj = Activator.CreateInstance(type,"张三",22);
                 return obj;
             }
            #endregion
    
            #region 05获得创建对象的方法和属性
             public static MethodInfo[] A_GetMethods(object obj) 
             {
                 MethodInfo[] mes = obj.GetType().GetMethods();
                 return mes;
             }
    
             public static MethodInfo[] B_GetMethod(object obj,string methodName)
             {
                 MethodInfo me = obj.GetType().GetMethod(methodName);
                 MethodInfo[] mes ={me};
                 return mes;
             }
    
             public static  PropertyInfo[] A_GetProperties(object obj)
             {
                 PropertyInfo [] prs = obj.GetType().GetProperties();
                 return prs;
             }
    
             public static PropertyInfo[] B_GetProperty(object obj, string proName)
             {
                 PropertyInfo pr = obj.GetType().GetProperty(proName);
                 PropertyInfo[] prs = { pr };
                 return prs;
             }
    
            #endregion
    
            #region 06获得属性方法
             public static void ShowMethods(MethodInfo[] mes) 
             {
                 foreach (MethodInfo item in mes)
                 {
                     Console.WriteLine(item.Name);
                 }
             }
    
             public static void ShowProperties(PropertyInfo[] pros)
             {
                 foreach (PropertyInfo item in pros)
                 {
                     Console.WriteLine(item.Name);
                 }
             }
            #endregion
        }
    }
    View Code

     dll 放置在对应的目录下的文件夹中

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  • 原文地址:https://www.cnblogs.com/YK2012/p/6751998.html
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