09.C#反射机制

class Program
{
    static void Main(string[] args)
    {
        Assembly assem = Assembly.Load("mscorlib");//加载系统程序集
        PrintInfo(assem);//输出程序集相关信息
        assem = Assembly.LoadFrom(@"F:\System.Data.SQLite.dll");//或使用LoadFile()方法
        PrintInfo(assem);//输出程序集相关信息
        assem = Assembly.GetExecutingAssembly();//获取当前执行代码的程序集
        PrintInfo(assem);//输出程序集相关信息
        Console.Read();
    }
    //输出程序集相关信息
    static void PrintInfo(Assembly assem)
    {
        Console.WriteLine("程序集全名:" + assem.FullName);
        Console.WriteLine("程序集的版本：" + assem.GetName().Version);
        Console.WriteLine("程序集初始位置:" + assem.CodeBase);
        Console.WriteLine("程序集位置：" + assem.Location);
        Console.WriteLine("程序集入口：" + assem.EntryPoint);
        Type[] types = assem.GetTypes();//得到该程序集里所有的类型
        Console.WriteLine("程序集下包含的类型数:" + types.Length);
        //foreach (var item in types)
        //{
        //    Console.WriteLine("类：" + item.Name);//输出类型名
        //}
        Console.WriteLine("============================\n");
    }
}

    class Program
    {
        static void Main(string[] args)
        {
            Assembly assembly = Assembly.Load("mscorlib");//加载程序集
            Module module = assembly.GetModule("CommonLanguageRuntimeLibrary");//得到指定模块
            Console.WriteLine("模块名："+module.Name);
            Type[] types = module.FindTypes(Module.FilterTypeName, "Assembly*");
            foreach (var item in types)
            {
                Console.WriteLine("类名：" + item.Name);//输出类型名
            }
            Console.Read();
        }
    }

class Myclass
{
    private int Id;
    public string Name;
    public void Method(int i) { }
}
class Program
{
    static void Main(string[] args)
    {
        Type type = typeof(Myclass);
        Console.WriteLine("类型名:" + type.Name);
        Console.WriteLine("类全名：" + type.FullName);
        Console.WriteLine("命名空间名:" + type.Namespace);
        Console.WriteLine("程序集名：" + type.Assembly);
        Console.WriteLine("模块名:" + type.Module);
        Console.WriteLine("基类名：" + type.BaseType);
        Console.WriteLine("是否类：" + type.IsClass);
        Console.WriteLine("类的公共成员：");
        MemberInfo[] memberInfos = type.GetMembers();//得到所有公共成员
        foreach (var item in memberInfos)
        {
            Console.WriteLine("成员类型：" + item.MemberType + "\t成员：" + item);
        }
        Console.Read();
    }
}

class Myclass
{
    public Myclass()
    {
        Console.WriteLine("创建Myclass对象！");
    }
    public void Method(int i)
    {
        Console.WriteLine("输出值：" + i);
    }
}
class Program
{
    static void Main(string[] args)
    {
        Type t = typeof(Myclass);//得到类型
        object o = Activator.CreateInstance(t);//创建类型的实例
        Console.WriteLine("已创建Myclass对象：" + o);
        MethodInfo method = t.GetMethod("Method");//获得实例的方法
        method.Invoke(o, new object[] { 100 });//调用方法
        Console.Read();
    }
}

class Program
{
    [Obsolete("已过时的方法！", true)]//把true改成false就可以编译通过
    static void OldMethod() { }
    static void Main(string[] args)
    {
        OldMethod();//调用过时的方法
        Console.Read();
    }
}

//自定义的Attribute类命名为XXXAttribute
class HelpAttribute : Attribute
{
    private String description;
    public HelpAttribute(String Descrition_in)
    {
        this.description = Descrition_in;
    }
    public String Description
    {
        get { return description; }
    }
}
class Program
{
    [Help("自定义特性")]//使用是不需要写“Attribute”后缀
    static void Main(string[] args)
    {
        Console.Read();
    }
}

[AttributeUsage(AttributeTargets.Method, AllowMultiple = false, Inherited = false)]
class HelpAttribute : Attribute
{
    private String description;
    public HelpAttribute(String Descrition_in)
    {
        this.description = Descrition_in;
    }
    public String Description
    {
        get { return description; }
    }
}
class Program
{
    [Help("自定义特性")]
    static void Main(string[] args)
    {
        Console.Read();
    }
}

[AttributeUsage(AttributeTargets.Method, AllowMultiple = true, Inherited = false)]
class HelpAttribute : Attribute
{
    private string _description;//可选参数
    public string _name;//命名参数
    public HelpAttribute(string description)
    {
        Console.WriteLine("HelpAttribute特性被创建！");
        this._description = description;
    }
    public string Description
    {
        get { return _description; }
    }
    public string Name
    {
        get { return _name; }
        set//命名参数,必须要有set方法
        {
            Console.WriteLine("属性：" + value);
            _name = value;
        }
    }
}
class Program
{
    [Help("自定义特性", Name = "李志伟")]//同时使用可选参数与命名参数
    static void Main(string[] args)
    {
        Console.Read();
    }
}

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true, Inherited = false)]
class HelpAttribute : Attribute
{
    private string _description;//可选参数
    private string _name;//命名参数
    public HelpAttribute(string description)
    {
        Console.WriteLine("====HelpAttribute特性被创建！====");
        this._description = description;
    }
    public string Description
    {
        get { return _description; }
    }
    public string Name
    {
        get { return _name; }
        set//命名参数,必须要有set方法
        {
            Console.WriteLine("====属性：" + value + "====");
            _name = value;
        }
    }
}
//使用了自定义特性的测试类
[Help("类上的自定义特性", Name = "lizhiwei")]
class TestClass
{
    [Help("方法上的自定义特性", Name = "李志伟1")]
    [Help("方法上的自定义特性", Name = "李志伟2")]
    public void TestMethod()
    {
        Console.WriteLine("===========测试方法===========");
    }
}
class Program
{
    static void Main(string[] args)
    {
        Type t = typeof(TestClass);
        //获取类上的自定义特性
        object[] obis = t.GetCustomAttributes(typeof(HelpAttribute), false);
        HelpAttribute attribute = obis[0] as HelpAttribute;
        Console.WriteLine("\n" + attribute.Description + "--" + attribute.Name + "\n");
        //获取方法上的自定义特性
        MethodInfo method = t.GetMethod("TestMethod");
        object[] methods = method.GetCustomAttributes(typeof(HelpAttribute), false);
        foreach (HelpAttribute help in methods)
        {
            Console.WriteLine("\n" + help.Description + "--" + help.Name + "\n");
        }
        Console.Read();
    }
}