delegate Demo (一个关于System.Timers.Timer的Demo)

namespace Delegates

{

    partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

            clock = new Clock(digital);

        }



        private void start_Click(object sender, System.EventArgs e)

        {

            this.clock.Start();

        }



        private void stop_Click(object sender, System.EventArgs e)

        {

            this.clock.Stop();

        }



        private Clock clock;

    }

}

Clock.cs类的内容

namespace Delegates

{

    using System.Windows.Forms;



    class Clock

    {

        public Clock(TextBox displayBox)

        {

            this.display = displayBox;

        }



        public void Start()

        {

            pulsed.Add(this.RefreshTime);

        }



        public void Stop()

        {

            pulsed.Remove(this.RefreshTime);

        }



        private delegate void InvokeCallback(string msg);

        private void RefreshTime(int hh, int mm, int ss)

        {

            if (!this.display.InvokeRequired)

            {

                this.display.Text = string.Format("{0:D2}:{1:D2}:{2:D2}", hh, mm, ss);

            }

            else

            {

                InvokeCallback msgCallback = new InvokeCallback(DisplayText);

                display.Invoke(msgCallback, new object[] { string.Format("{0:D2}:{1:D2}:{2:D2}", hh, mm, ss) });



            }



        }



        private void DisplayText(string text)

        {

            this.display.Text = text;

        }



        private Ticker pulsed = new Ticker();

        private TextBox display;







    }

}

 

namespace Delegates

{

    using System.Collections;

    using System.Timers;

    using System.Windows.Forms;



    class Ticker

    {

        public delegate void Tick(int hh, int mm, int ss);



        public Ticker()

        {

            this.ticking.Elapsed += new ElapsedEventHandler(this.OnTimedEvent);

            this.ticking.Interval = 1000; // 1 second

            this.ticking.Enabled = true;

        }



        public void Add(Tick newMethod)

        {

            this.tickers += newMethod;

        }



        public void Remove(Tick oldMethod)

        {

            this.tickers -= oldMethod;

        }



        private void Notify(int hours, int minutes, int seconds)

        {

            if (this.tickers != null)

            {

                this.tickers(hours, minutes, seconds);

            }



        }



        private void OnTimedEvent(object source, ElapsedEventArgs args)

        {

            int hh = args.SignalTime.Hour;

            int mm = args.SignalTime.Minute;

            int ss = args.SignalTime.Second;

            Notify(hh, mm, ss);

        }



        private Tick tickers;

        private System.Timers.Timer ticking = new System.Timers.Timer();

    }

}

 

Ticker.cs类的内容