我这里有个在窗体上可以写字的例子，不能保存



namespace WriteWords

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }



        //MyPoint1, MyPoint2表示鼠标按下和弹起时鼠标的坐标位置

        public Point MyPoint1, MyPoint2;

        public int MyFlag = 0;



        private void Form1_MouseUp(object sender, MouseEventArgs e)

        {

            //当鼠标弹起时，设置MyFlag = 0，表示不能画线

            this.MyFlag = 0;

        }



        private void Form1_MouseMove(object sender, MouseEventArgs e)

        {

            this.Text = "X=" + e.X.ToString() + ",Y=" + e.Y.ToString();

            Graphics g = this.CreateGraphics();

            Pen MyPen = new Pen(Color.Black);



            //MyFlag=0表示鼠标弹起，不能进行画线

            //当鼠标按下时，设置MyFlag=1表示可以画线

            if (this.MyFlag == 0)

                return;



            //鼠标移动，每次变换时，MyPoint2都记录下鼠标的位置，以便进行鼠标移动画线

            this.MyPoint2.X = e.X;

            this.MyPoint2.Y = e.Y;

            g.DrawLine(MyPen, MyPoint1.X, MyPoint1.Y, MyPoint2.X, MyPoint2.Y);



            //当画完一条线后（很短的，可以当做一个小点看待），将MyPoint1的坐标重置为此时鼠标的位置

            MyPoint1.X = e.X;

            MyPoint1.Y = e.Y;

        }



        private void Form1_MouseDown(object sender, MouseEventArgs e)

        {

            //鼠标第一次按下时，设置鼠标坐标为第一个点的坐标

            this.MyFlag = 1;

            this.MyPoint1.X = e.X;

            this.MyPoint1.Y = e.Y;

        }



    }

}

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;



namespace HandDrawing

{

    public partial class HandDrawing : Form

    {

        public HandDrawing()

        {

            InitializeComponent();

            m_lines = new List<List<Point>>();

        }



        private List<List<Point>> m_lines;

        private List<Point> m_newLine;



        private void Form1_MouseDown(object sender, MouseEventArgs e)

        {

            m_newLine = new List<Point>();

        }



        private void Form1_MouseMove(object sender, MouseEventArgs e)

        {

            m_addPoint(e.X, e.Y);

        }



        private void Form1_MouseUp(object sender, MouseEventArgs e)

        {

            m_addPoint(e.X, e.Y);

            m_lines.Add(m_newLine);

        }



        private void m_addPoint(int x, int y)

        {

            m_newLine.Add(new Point(x, y));

            int points = m_newLine.Count;

            if (points > 1)

            {

                Graphics g = this.CreateGraphics();

                Pen p = new Pen(Color.Black);

                g.DrawLine(p, m_newLine[points - 2].X, m_newLine[points - 2].Y, m_newLine[points - 1].X, m_newLine[points - 1].Y);

                p.Dispose();

                g.Dispose();

            }

        }



        private void Form1_Paint(object sender, PaintEventArgs e)

        {

            DrawAllLines(e.Graphics);

        }



        private void DrawAllLines(Graphics g)

        {

            Pen p = new Pen(Color.Black);

            int TotalLines = m_lines.Count;

            for (int i = 0; i < TotalLines; i++)

            {

                g.DrawLines(p, m_lines[i].ToArray());

            }

            p.Dispose();

            g.Dispose();

        }



        private void miClear_Click(object sender, EventArgs e)

        {

            //foreach (List<Point> l in m_lines)

            //    l.Clear();

            m_lines.Clear();

            this.Invalidate();

        }



        private void miSave_Click(object sender, EventArgs e)

        {

            if (saveFileDialog1.ShowDialog() != DialogResult.OK)

                return;

            Bitmap bmp = null;

            Graphics g = null;

            Brush b = null;

            try

            {

                bmp = new Bitmap(this.ClientSize.Width, this.ClientSize.Height);

                g = Graphics.FromImage(bmp);

                b = new SolidBrush(Color.White);

                g.FillRectangle(b, this.ClientRectangle);

                DrawAllLines(g);

                bmp.Save(saveFileDialog1.FileName, System.Drawing.Imaging.ImageFormat.Bmp);

            }

            catch (Exception ex)

            {

                MessageBox.Show(string.Format("Cannot save picture,error message:{0}", ex.Message), "Error", MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);

            }

            finally

            {

                if (bmp != null)

                    bmp.Dispose();

                if (g != null)

                    g.Dispose();

                if (b != null)

                    b.Dispose();

            }

        }



        private void miExit_Click(object sender, EventArgs e)

        {

            Application.Exit();

        }

    }

}