C#泛型和反射实例解析

public T abc<T>(T word){return word;return default(T); //关键字default可以对引用类型返回nullAble,int类型返回0,初始化一个T的感觉啦}abc<string>("x");//struct 是 值类型 //好处调用的是如果参数是值类型可以不用著名 test(100) 而不需要 test<int>(100);public void test<T>(T number) where T : struct{int z = Convert.ToInt32(number);//调用 test(100);}//下面的不知道好处在哪用在什么地方,public void test2<T>(T lei) where T : class{} public void test3<T>() where T : stooges{} public T test4<T>() where T : new(){T abc = new T();return abc;}public class stooges{   }

for(var attr in object) { object[attr]=value, attr = attr } var obj = new abc();Type T = typeof(abc); //typeof(Class) 而不是 typeof(object) 哦Type V = obj.GetType(); //obj.GetType() 就是typeof(object的class)PropertyInfo[] attrs = obj.GetType().GetProperties(BindingFlags.Instance | BindingFlags.Public); //获取attrsforeach (PropertyInfo attr in attrs) {string key = attr.Name; //获取attr nameobject value = attr.GetValue(obj, null); //获取value  Type type = attr.PropertyType; //类型    }

T.GetProperty("key").GetValue(obj, null); //read a key valueT.GetProperty("key").SetValue(obj, "", null); //write a value to key//注意如果是字典 T.GetProperty("Item").GetValue(obj, new [] {"id"}); //先拿Item 然后才通过 new[] {这里放指定的key}

class MyClass{public int x { get; set; }public int y { get; set; }public MyClass(int i){  x = y + i;}public MyClass(int i, int j){  x = i;  y = j;}public int sum(){  return x + y;}}

Type t = typeof(MyClass);     ConstructorInfo[] constructors = t.GetConstructors(); //使用这个方法获取构造函数列表    for (int i = 0; i < constructors.Length; i++){ConstructorInfo constructor = constructors[i];//构造函数也是方法所以有 GetParametersParameterInfo[] parameters = constructor.GetParameters(); //获取当前构造函数的参数列表string paraTypeName = parameters[0].ParameterType.Name; //方法的参数类型名称string paraName = parameters[0].Name;// 方法的参数名         }     //调用构造函数object[] args = new object[2];args[0] = 10;args[1] = 20;//不用new 直接实例化object instance = constructors[0].Invoke(args); //实例化一个这个构造函数有两个参数的类型对象,如果参数为空，则为nullobject instance = (t)Activator.CreateInstance(t); 还有这种实例的方法,不清楚可以放参数没有

MethodInfo[] methods = T.GetMethods(BindingFlags.Public | BindingFlags.DeclaredOnly | BindingFlags.Instance);foreach (MethodInfo method in methods){string return_name = method.ReturnType.Name; //返回方法的返回类型string name = method.Name;if (name.Equals("sum", StringComparison.Ordinal)) //指定方法名调用{  int value = (int)method.Invoke(instance, null); //instance是之前实例好的对象,方法就是在这个对象之中}}

Type t = typeof(MyClass);Console.WriteLine("----------------Method------------------");MethodInfo[] methods = t.GetMethods();foreach (MethodInfo method in methods){  Console.WriteLine("Method:" + method);  //Console.WriteLine(method);   //Console.WriteLine("返回值：" + method.ReturnParameter); }Console.WriteLine("---------------Field-------------------"); //字段 ,比如这种 private static string name; FieldInfo[] fields = t.GetFields(BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static);foreach (FieldInfo field in fields){  Console.WriteLine("Field:" + field);}Console.WriteLine("--------------Member--------------------"); //成员即方法和属性MemberInfo[] members = t.GetMembers();foreach (MemberInfo member in members){  Console.WriteLine("Member:" + member);}Console.WriteLine("--------------Property--------------------"); //属性PropertyInfo[] properties = t.GetProperties();foreach (PropertyInfo property in properties){  Console.WriteLine("Property:" + property);}Console.WriteLine("--------------Constructor--------------------"); //构造函数ConstructorInfo[] constructors = t.GetConstructors(BindingFlags.NonPublic | BindingFlags.Instance);foreach (ConstructorInfo constructor in constructors){  Console.WriteLine("Constructor:" + constructor);}