C#实现钟表程序设计

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;
using System.Diagnostics;
 
 
namespace 钟表
{
    public partial class frmMain : Form
    {
        bool flsMouseDown = false;
        Point fDownPosition;
        public frmMain()
        {
            InitializeComponent();
        }
        private void ctsmiExit_Click(object sender, EventArgs e)
        {
            this.Close();
        }
        private void frmMain_MouseDown(object sender, MouseEventArgs e)
        {
            if (e.Button == MouseButtons.Left)
            {
                flsMouseDown = true;
                fDownPosition = e.Location;
                //Debug.WriteLine(e.Location);
            }
        }
        private void frmMain_MouseMove(object sender, MouseEventArgs e)
        {
            if (flsMouseDown)
            {
                this.Left = this.Location.X + (e.X - fDownPosition.X);
                this.Top = this.Location.Y + (e.Y - fDownPosition.Y);
 
            }
        }
        private void frmMain_Mouseup(object sender, MouseEventArgs e)
        {
            flsMouseDown = false;
        }
        private void tmrMain_Tick(object sender, EventArgs e)
        {
            this.Refresh();//调用窗体的Paint事件，根据调制的时间来刷新paint时间
        }
        private void fDrawDot(Graphics aGraphics, double aValue, int aRadius)//画出表盘刻度
        {
            double lAngle = ((360 - aValue * 6) + 90) * Math.PI / 180;//根据角度绘画
            Point lPoint = new Point((int)(200 + 180 * Math.Cos(lAngle)),//刻度所在的为值
                                    (int)(200 - 180 * Math.Sin(lAngle)));
            aGraphics.FillEllipse(Brushes.Black, new Rectangle(lPoint.X - aRadius,//FillEllipse为内部填充颜色方法，Rectangle为绘画圆，前俩为圆心坐标，后俩为宽和高
                                    lPoint.Y - aRadius, 2 * aRadius, 2 * aRadius));
        }
        private void fDrawLine(Graphics aGraphics, double aValue, double aLength, Pen aPen)//画出时，分，秒的线
        {//aValue为角度值，小时12个刻度每个占30°，分和秒60个刻度每个站6°avalue按照的是一个圆分成60个换成角度乘于6
            //aLength是指针的长度
            double lAngle = ((360 - aValue * 6) + 90) * Math.PI / 180;//角度转化为数值
            Point lPoint = new Point((int)(200 + aLength * Math.Cos(lAngle)),//指针线的终点，坐标x，y通过直角三角求得
                        (int)(200 - aLength * Math.Sin(lAngle)));
            aGraphics.DrawLine(aPen, new Point(200, 200), lPoint);//绘制俩点连成一条直线，起点相同都为（200,200）
        }
        private void frmMain_Paint(object sender, PaintEventArgs e)
        {
            e.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;//使指针转动显得平滑
            e.Graphics.DrawImage(this.BackgroundImage, 0, 0, 400, 400);//规定表盘的大小和位置
            for (int i = 0; i < 60; i++)
                if (i % 5 == 0) fDrawDot(e.Graphics, i, 6);//绘制钟表刻度，大点和小点
                else fDrawDot(e.Graphics, i, 2);
            DateTime dt = DateTime.Now;//获取时间
            Pen pSecond = new Pen(Color.Black, 2);
            Pen pMinute = new Pen(Color.Red, 2);
            Pen pHour = new Pen(Color.Blue, 4);
            fDrawLine(e.Graphics, ((dt.Hour % 12) + dt.Minute / 60.0) * 5, 100, pHour);//绘画时，分，秒指针
            fDrawLine(e.Graphics, dt.Minute+dt.Second/60.0,160, pMinute);
            fDrawLine(e.Graphics, dt.Second+dt.Millisecond/1000.0, 170, pSecond);
        }

this.DoubleBuffered = true;
            this.Deactivate += new System.EventHandler(this.ctsmiExit_Click); 
            this.Paint += new System.Windows.Forms.PaintEventHandler(this.frmMain_Paint);
            this.MouseDown += new System.Windows.Forms.MouseEventHandler(this.frmMain_MouseDown);
            this.MouseMove += new System.Windows.Forms.MouseEventHandler(this.frmMain_MouseMove);
            this.MouseUp += new System.Windows.Forms.MouseEventHandler(this.frmMain_Mouseup);