数字时钟DigClock

首先建立数字显示类:

using System;
using System.Drawing;

namespace CsDev
{
    class SevenSegmentDispay
    {
        Graphics grph;
        //0,1,2,3,4,5,6,7,8,9
        static byte[,] bySegment = { { 1, 1, 1, 0, 1, 1,1 }, { 0, 0, 1, 0, 0,1, 0 },
                                     {1,0,1,1,1,0,1},{1,0,1,1,0,1,1},
                                     {0,1,1,1,0,1,0},{1,1,0,1,0,1,1},
                                     {1,1,0,1,1,1,1},{1,0,1,0,0,1,0},
                                     {1,1,1,1,1,1,1},{1,1,1,1,0,1,1}};
        readonly Point[][] apt = new Point[7][];

        public SevenSegmentDispay(Graphics grph)
        {
            this.grph = grph;
            apt[0] = new Point[] { new Point(3, 2), new Point(39, 2), new Point(31, 10), new Point(11, 10) };
            apt[1] = new Point[] { new Point(2, 3), new Point(10, 11), new Point(10, 31), new Point(2, 35) };
            apt[2] = new Point[] { new Point(40, 3), new Point(40, 35), new Point(32, 31), new Point(32, 11) };
            apt[3] = new Point[] { new Point(3, 36), new Point(11, 32), new Point(31, 32), new Point(39, 36),
                                    new Point(31, 40),new Point(11, 40)};
            apt[4] = new Point[] { new Point(2, 37), new Point(10, 41), new Point(10, 61), new Point(2, 69) };
            apt[5] = new Point[] { new Point(40, 37), new Point(40, 69), new Point(32, 61), new Point(32, 41) };
            apt[6] = new Point[] { new Point(11, 62), new Point(31, 62), new Point(39, 70), new Point(3, 70) };
        }

        public SizeF MeasureString(string str, Font font)
        {
            SizeF sizef = new SizeF(0, grph.DpiX * font.SizeInPoints / 72);

            for (int i = 0; i < str.Length; i++)
            {
                if (Char.IsDigit(str[i]))
                    sizef.Width += 42 * grph.DpiX * font.SizeInPoints / 72 / 72;
                else if (str[i] == ':')
                    sizef.Width += 12 * grph.DpiX * font.SizeInPoints / 72 / 72;
            }
            return sizef;
        }
        void Fill(Point[] apt, Font font, Brush brush, float x, float y)
        {
            PointF[] aptf = new PointF[apt.Length];
            for (int i = 0; i < apt.Length; i++)
            {
                aptf[i].X = x + apt[i].X * grph.DpiX * font.SizeInPoints / 72 / 72;
                aptf[i].Y = y + apt[i].Y * grph.DpiY * font.SizeInPoints / 72 / 72;
            }
            grph.FillPolygon(brush, aptf);
        }
        float Number(int num, Font font, Brush brush, float x, float y)
        {
            for (int i = 0; i < apt.Length; i++)
                if (bySegment[num, i] == 1)
                    Fill(apt[i], font, brush, x, y);
            return x + 42 * grph.DpiX * font.SizeInPoints / 72 / 72;
        }
        float Colon(Font font, Brush brush, float x, float y)//画冒号
        {
            Point[][] apt = new Point[2][];
            apt[0] = new Point[] { new Point(2, 21), new Point(6, 17), new Point(10, 21), new Point(6, 25) };
            apt[1] = new Point[] { new Point(2, 51), new Point(6, 47), new Point(10, 51), new Point(6, 55) };
            for (int i = 0; i < apt.Length; i++)
                Fill(apt[i], font, brush, x, y);
            return x + 12 * grph.DpiX * font.SizeInPoints / 72 / 72;
        }
        public void DrawString(string str, Font font, Brush brush, float x, float y)
        {
            for (int i = 0; i < str.Length; i++)
            {
                if (Char.IsDigit(str[i]))
                    x = Number(str[i] - '0', font, brush, x, y);
                else if (str[i] == ':')
                    x = Colon(font, brush, x, y);
            }
        }
    }
}

实现类:

using System;
using System.Windows.Forms;
using System.Drawing;
using System.Globalization;

namespace CsDev
{
    class DigClock:Form
    {
        DateTime dt;
        public static void Main()
        {
            Application.Run(new DigClock());
        }
        public DigClock()
        {
            Text = "数字时钟";
            ResizeRedraw = true;
            MinimumSize = SystemInformation.MinimumWindowSize + new Size(0, 1);

            dt = DateTime.Now;
            Timer timer = new Timer();
            timer.Tick+=new EventHandler(timer_Tick);
            timer.Interval = 100;
            timer.Enabled = true;
        }
        void timer_Tick(object obj, EventArgs e)
        {
            DateTime dtNow = DateTime.Now;
            dtNow = new DateTime(dtNow.Year, dtNow.Month, dtNow.Day, dtNow.Hour, dtNow.Minute, dtNow.Second);
            if (dt != dtNow)
            {
                dt = dtNow;
                Invalidate();
            }
        }
        protected override void OnPaint(PaintEventArgs e)
        {
            SevenSegmentDispay ssd = new SevenSegmentDispay(e.Graphics);
            string strTime = dt.ToString("T",DateTimeFormatInfo.InvariantInfo);
            SizeF sizef = ssd.MeasureString(strTime, Font);
            float fScale = Math.Min(ClientSize.Width/sizef.Width,ClientSize.Height/sizef.Height);
            Font font = new Font(Font.FontFamily, fScale * Font.SizeInPoints);
            sizef = ssd.MeasureString(strTime, font);//注意font是自定义

            ssd.DrawString(strTime, font, Brushes.Red, (ClientSize.Width-sizef.Width)/2,(ClientSize.Height-sizef.Height)/2);
            base.OnPaint(e);
        }
    }
}

效果图: