关于Attribute的一些学习

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namespace Con_Attribute{    /// <summary>    ///  "Sports" 是给构造函数的赋值， Level = 5 是给属性的赋值。    /// </summary>    [HobbyAttribute("Sports", Level = 5)]    class Student    {        public string profession;        public string Profession        {            get { return profession; }            set { profession = value; }        }    }    class HobbyAttribute : System.Attribute    {        //兴趣类型        private string type;        public string Type        {            get { return type; }            set { type = value; }        }        //兴趣指数        private int level;        public int Level        {            get { return level; }            set { level = value; }        }        /// <summary>        /// 构造函数        /// </summary>        /// <remarks>参数值为null的string 危险，所以必需在构造函数中赋值</remarks>        /// <param name="_type"></param>        public HobbyAttribute(string _type)        {            this.Type = _type;        }    }}

下面我们来调用一下看看效果：

 class Program    {        static void Main(string[] args)        {            #region demo2            //通过反射得到Student类的信息            System.Reflection.MemberInfo info = typeof(Student);            HobbyAttribute hobbyatt = (HobbyAttribute)Attribute.GetCustomAttribute(info, typeof(HobbyAttribute));            if (hobbyatt != null)            {                Console.WriteLine("类名：{0}", info.Name);                Console.WriteLine("兴趣类型：{0}", hobbyatt.Type);                Console.WriteLine("兴趣指数：{0}", hobbyatt.Level.ToString());                Console.Read();            }            #endregion        }    }

运行结果如下：

或许我们能做些事情，比如页面权限控制。通过Attribute得到该页面.cs类的信息，然后去数据库里面的权限部分匹配，嗯，只是一个思路吧，回头再看看其它效果。

//属性测试//[TestAttribute(ccvalue="hello")]public class AATest : UIButton{public AATest (){}}//[AttributeUsage(AttributeTargets.Method|AttributeTargets.Class)] [AttributeUsage(AttributeTargets.Method, AllowMultiple = false)] //TestAttribute类仅作用在方法上public class TestAttribute : Attribute{public string Role{ get; set;}public TestAttribute(string role){this.Role = role;}public TestAttribute(){}}public class SysDataManager{public SysDataManager(){}[TestAttribute("anyone")]public void ShowInfo(){Utils.Tools.Alert ("anyone:ShowInfo()");}[TestAttribute("admin")]public void Out2Excel(){Utils.Tools.Alert ("admin:Out2Excel()");}public void DeleteInfo(){Utils.Tools.Alert ("DeleteInfo()");}}public static class OperationInvoker{public static void Invoke(object target, string role, string operationName, object[] param){var methordinfo = target.GetType ().GetMethod (operationName); //获取所有方法if (methordinfo.IsDefined (typeof(TestAttribute), false)) {var permissons = methordinfo.GetCustomAttributes (typeof(TestAttribute), false).OfType<TestAttribute> ();if (permissons.Any (x => x.Role == role)) {methordinfo.Invoke (target, param);} else {//Console.WriteLine (string.Format ("{0}", role, operationName));Utils.Tools.Alert (string.Format ("角色{0}没有访问操作{1}的权限！", role, operationName));//throw new Exception (string.Format ("角色{0}没有访问操作{1}的权限！", role, operationName));}}}//...}