C#類對象的事件定義

1. 類對象代碼

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

namespace WinformEventTest
{
    /// <summary>
    /// 定義了一個 ShowString 事件的對象類
    /// </summary>
    internal class EventClass
    {
        /// <summary>  
        /// 聲明委托  
        /// </summary>  
        /// <param name="a">委托傳遞的參數</param>  
        public delegate void BroadcastEventHander(string a);
        /// <summary>
        /// 聲明委托相關的事件
        /// </summary>
        public event BroadcastEventHander Broadcast;

        /// <summary>
        /// 聲明定時器
        /// </summary>
        private Timer _timer;

        /// <summary>
        /// 
        /// </summary>
        public EventClass()
        {
            _timer = new Timer(1000);
            _timer.Elapsed += new ElapsedEventHandler(Timer_Elapsed);
            _timer.Enabled = true;
        }

        /// <summary>
        /// 內部定時器事件，用於模擬產生事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        void Timer_Elapsed(object sender, ElapsedEventArgs e)
        {
            try
            {
                Broadcast("來自 EventClass 對象事件的消息：" + DateTime.Now.ToString()); // 產生事件
            }
            catch (Exception)
            {

            }
        }
    }
}

 

2.Winform調用舉例

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WinformEventTest
{
    public partial class Form1 : Form
    {
        // 聲明變量
        EventClass _eventClass;

        /// <summary>  
        /// 控制台打印字符串
        /// </summary>  
        /// <param name="a"></param>  
        public void ConsoleShowTxt(string a)
        {
            Console.WriteLine(DateTime.Now.ToString() + " | " + a + "\n");
        }
        
        public Form1()
        {
            InitializeComponent();

            // Member initialize
            _eventClass = new EventClass();

            // Member event initialize
            _eventClass.Broadcast += new EventClass.BroadcastEventHander(ConsoleShowTxt); // 委托類事件（Broadcast）綁定實際處理方法（ConsoleShowTxt）
        }
    }
}