委托与事件

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Sample_CUI
{
    namespace Delegate_And_Event
    {
        /* 场景
        XXX收到一个解决方案（内网建设方案），是否采用这个方案需要经过2个过程。
        第一个过程（资料确认）：需要技术部中User1和User2确认。
        第二个过程（最终确认）：需要CTO和CEO确认。

        PS：过程中的确认人数和来自的部门也不同，过程有进展要通知相关的人员进行确认。
        */

        /// <summary>
        /// 通知事件
        /// </summary>
        public class WorkNoticeEventArgs : EventArgs
        {
            /// <summary>
            /// 要通知的人
            /// </summary>
            public readonly List<string> users;

            public WorkNoticeEventArgs(List<string> users)
            {
                this.users = users;
            }
        }

        /// <summary>
        /// 确认委托
        /// </summary>
        /// <param name="sender">确认方法</param>
        /// <param name="e">通知事件</param>
        public delegate void WorkNoticeEventHandler(object sender,WorkNoticeEventArgs e);


        /// <summary>
        /// 资料确认
        /// </summary>
        public class ProcessDataValidation
        {
            //声明事件
            public event WorkNoticeEventHandler Begin = null;
            public event WorkNoticeEventHandler User1Validated = null;
            public event WorkNoticeEventHandler User2Validated = null;
            public event WorkNoticeEventHandler Finished = null;

            //是否确认
            private bool user1Validated, user2Validated;

            #region Method

            /// <summary>
            /// 过程开始
            /// </summary>
            /// <param name="users"></param>
            public virtual void OnBegin(List<string> users)
            {
                //do something
                Console.WriteLine("Begin[{0}]",
                    this.ToString().Substring(this.ToString().LastIndexOf('.') + 1)
                    );
                if (Begin != null)
                {
                    WorkNoticeEventArgs e = new WorkNoticeEventArgs(users);
                    Begin(this,e);//调用订阅此事件的方法
                }
            }

            /// <summary>
            /// User1确认
            /// </summary>
            /// <param name="users"></param>
            public virtual void OnUser1Validate(List<string> users)
            {
                //do something
                user1Validated = true;
                Console.WriteLine("Use1 has been validated[{0}]",
                    this.ToString().Substring(this.ToString().LastIndexOf('.') + 1)
                    );
                WorkNoticeEventArgs e = new WorkNoticeEventArgs(users);
                User1Validated(this, e);//调用订阅此事件的方法
            }

            /// <summary>
            /// User2确认
            /// </summary>
            /// <param name="users"></param>
            public virtual void OnUser2Validate(List<string> users)
            {
                //do something
                user2Validated = true;
                Console.WriteLine("Use2 has been validated[{0}]",
                    this.ToString().Substring(this.ToString().LastIndexOf('.') + 1)
                    );
                WorkNoticeEventArgs e = new WorkNoticeEventArgs(users);
                User2Validated(this, e);//调用订阅此事件的方法
            }

            /// <summary>
            /// 过程完成
            /// </summary>
            /// <param name="users"></param>
            public virtual void OnFinish(List<string> users)
            {
                if (user1Validated && user2Validated)
                {
                    //do something
                    Console.WriteLine("Finish[{0}]",
                        this.ToString().Substring(this.ToString().LastIndexOf('.') + 1)
                        );
                    WorkNoticeEventArgs e = new WorkNoticeEventArgs(users);
                    Finished(this,e);//调用订阅此事件的方法
                }
            }

            #endregion

        }//class ProcessDataValidation


        /// <summary>
        /// 资料确认子类
        /// </summary>
        public class ProcessDataValidate_NonNetSolution : ProcessDataValidation
        {
            /// <summary>
            /// 改写父类方法
            /// </summary>
            /// <param name="users"></param>
            public override void OnBegin(List<string> users)
            {
                //do something
                users.Clear();
                users.Add("Jie");
                base.OnBegin(users);
            }
        }//class ProcessDataValidate_NonNetSolution

        /// <summary>
        /// 工作通知 监视者
        /// </summary>
        public class WorkNoticeObserver
        {
            public void NoticeUsersWhenProcessBegin(object sender, WorkNoticeEventArgs e)
            {
                Console.Write("Notice:");
                for (int i = 0; i < e.users.Count; i++)
                {
                    Console.Write("{0} ", e.users[i]);
                }
                Console.WriteLine();
                Console.WriteLine();
            }

            public void NoticeUsersWhenUser1Validated(object sender, WorkNoticeEventArgs e)
            {
                Console.Write("Notice:");
                for (int i = 0; i < e.users.Count; i++)
                {
                    Console.Write("{0} ", e.users[i]);
                }
                Console.WriteLine();
                Console.WriteLine();
            }

            public void NoticeUsersWhenUser2Validated(object sender, WorkNoticeEventArgs e)
            {
                Console.Write("Notice:");
                for (int i = 0; i < e.users.Count; i++)
                {
                    Console.Write("{0} ", e.users[i]);
                }
                Console.WriteLine();
                Console.WriteLine();
            }

            public void NoticeUsersWhenProcessFinished(object sender, WorkNoticeEventArgs e)
            {
                Console.Write("Notice:");
                for (int i = 0; i < e.users.Count; i++)
                {
                    Console.Write("{0} ", e.users[i]);
                }
                Console.WriteLine();
                Console.WriteLine();
            }

        }//class WorkNoticeObserver


        public class SampleTest
        {
            public static void Test()
            {
                List<string> list1 = new List<string>();
                list1.Add("User1");
                list1.Add("User2");
                list1.Add("CTO");
                list1.Add("CEO");

                List<string> list2 = new List<string>();
                list2.Add("User2");

                List<string> list3 = new List<string>();
                list3.Add("User1");

                List<string> list4 = new List<string>();
                list4.Add("CTO");
                list4.Add("CEO");

                WorkNoticeObserver wn = new WorkNoticeObserver();
                ProcessDataValidation p = new ProcessDataValidation();
                //注册事件
                p.Begin += new WorkNoticeEventHandler(wn.NoticeUsersWhenProcessBegin);
                p.User1Validated += new WorkNoticeEventHandler(wn.NoticeUsersWhenUser1Validated);
                p.User2Validated += new WorkNoticeEventHandler(wn.NoticeUsersWhenUser2Validated);
                p.Finished += new WorkNoticeEventHandler(wn.NoticeUsersWhenProcessFinished);

                //触发事件
                p.OnBegin(list1);
                p.OnUser1Validate(list2);
                p.OnUser2Validate(list3);
                p.OnFinish(list4);

                p = null;
                p = new ProcessDataValidate_NonNetSolution();
                // 子类Begin事件的实现
                p.Begin += delegate(object sender, WorkNoticeEventArgs e) {
                    Console.Write("Notice:");
                    for (int i = 0; i < e.users.Count; i++)
                    {
                        Console.Write("{0} ", e.users[i]);
                    }
                    Console.WriteLine();
                };

                p.OnBegin(list2);
            }

        }//class SampleTest

    }//namespace Delegate_And_Event
}