ASP.NET图形编程部分示例

        Page_Load#region Page_Load
        private void Page_Load(object sender, System.EventArgs e)
        {
            // 在此处放置用户代码以初始化页面
            if(! IsPostBack)
            {
                string _ChartType = "";
                if(Request.QueryString["ChartType"] != null && Request.QueryString["ChartType"].Trim().Length > 0)
                {
                    _ChartType = Request.QueryString["ChartType"].Trim();
                }
                switch( _ChartType )
                {
                    case "Line"://画直线
                        ShowLine();
                        break;
                    case "Rectangle"://画矩形
                        ShowRectangle();
                        break;
                    case "FRectangle"://填充矩形
                        FillRectangle();
                        break;
                    case "Rectangles"://画矩形组
                        ShowRectangles();
                        break;
                    case "FRectangles"://填充矩形组
                        FillRectangles();
                        break;
                    case "Polygon"://画多边形
                        ShowPolygon();
                        break;
                    case "Ellipse"://画椭圆
                        ShowEllipse();
                        break;
                    case "FEllipse"://填充椭圆
                        FillEllipse();
                        break;
                    case "String"://画文字
                        ShowString();
                        break;
                    case "Arc"://画弧形
                        ShowArc();
                        break;
                    case "Pie"://画扇形
                        ShowPie();
                        break;
                    case "FPie"://填充扇形
                        FillPie();
                        break;
                    default:
                        ShowLine();
                        break;
                }
            }
        }
        #endregion

        //画直线
        ShowLine#region ShowLine
        private void ShowLine()
        {
            //创建Graphics对象
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _ghG = Graphics.FromImage( _bmImage );
            //清除整个绘图面并以指定背景色填充
            _ghG.Clear( Color.Wheat );
            //创建画笔
            Pen _penRed = new Pen( Color.Red, 5);
            //=====================
            //绘制一条连接由坐标对指定的两个点的线条
            _ghG.DrawLine( _penRed,10,10,200,10 );
            //==========================
            //将此图像以指定的格式保存到指定的流中
            _bmImage.Save( Response.OutputStream,System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _ghG.Dispose();
        }
        #endregion

        //画矩形
        ShowRectangle#region ShowRectangle
        private void ShowRectangle()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _ghG = Graphics.FromImage( _bmImage );
            _ghG.Clear( Color.Wheat  );
            Pen _penRed = new Pen( Color.Red, 5);
            //=============
            _ghG.DrawRectangle( _penRed, 10, 10, 20, 150);
            //=================
            _bmImage.Save( Response.OutputStream,System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _ghG.Dispose();
        }
        #endregion

        //画矩形组
        ShowRectangles#region ShowRectangles
        private void ShowRectangles()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _ghG = Graphics.FromImage( _bmImage );
            _ghG.Clear( Color.Wheat );
            Pen _penRed = new Pen( Color.Red, 1);
            //=====================
            Rectangle[] _rect = new Rectangle[5];

            int _left = 10;
            int _width = 10;
            int _space = 10;
            int _level = 250;

            for( int index = 0; index < _rect.Length; index++)
            {
                _rect[index] = new Rectangle();
                _rect[index].X = _left + index * ( _width + _space);
                _rect[index].Y = _level - 15 * index;
                _rect[index].Width = _width;
                _rect[index].Height =  15 * index;
            }
            _ghG.DrawRectangles( _penRed, _rect);

            _ghG.DrawLine( _penRed,_left,_level,250,_level);
            //=====================
            _bmImage.Save( Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _ghG.Dispose();
        }
        #endregion

        //画多边形
        ShowPolygon#region ShowPolygon
        private void ShowPolygon()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _ghG = Graphics.FromImage( _bmImage );
            _ghG.Clear(  Color.Wheat );
            Pen _penRed = new Pen( Color.Red, 5);
            //========
            Point _p1 = new Point(100,100);
            Point _p2 = new Point(150,100);
            Point _p3 = new Point(100,200);
            _ghG.DrawPolygon( _penRed, new Point[]{_p1,_p2,_p3} );
            //==============
            _bmImage.Save(Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _ghG.Dispose();
        }
        #endregion

        //画椭圆
        ShowEllipse#region ShowEllipse
        private void ShowEllipse()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            Pen _penRed = new Pen( Color.Red, 5);
            //===================
            _gpG.DrawEllipse( _penRed,10,20,100,75);
            //====================
            _bmImage.Save( Response.OutputStream,System.Drawing.Imaging.ImageFormat.Gif);
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion

        //画文字
        ShowString#region ShowString
        private void ShowString()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            //===================
            string _String = "Study GDI";
            Font _font = new Font("宋体",12F);
            SolidBrush _brush = new SolidBrush( Color.Red );
            _gpG.DrawString( _String, _font, _brush, 20,50);
            //====================
            _bmImage.Save( Response.OutputStream,System.Drawing.Imaging.ImageFormat.Gif);
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion

        //画弧形
        ShowArc#region ShowArc
        private void ShowArc()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            Pen _penRed = new Pen(Color.Red, 5);
            //=================================
            Rectangle _rect = new Rectangle(10,10,150,150);
            _gpG.DrawArc(_penRed, _rect,0,270);
            //=================================
            _bmImage.Save( Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion

        //画扇形
        ShowPie#region ShowPie
        private void ShowPie()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            Pen _penRed = new Pen(Color.Red, 5);
            //=================================
            Rectangle _rect = new Rectangle(10,10,150,150);
            _gpG.DrawPie(_penRed, _rect,0,270);
            //=================================
            _bmImage.Save( Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion

        //填充矩形
        FillRectangle#region FillRectangle
        private void FillRectangle()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            SolidBrush _brush = new SolidBrush( Color.Black );
            //=======================================
            _gpG.FillRectangle( _brush, 10,10,100,150);
            //======================================
            _bmImage.Save( Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion

        //填充矩形组
        FillRectangles#region FillRectangles
        private void FillRectangles()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            SolidBrush _brush = new SolidBrush( Color.Black );
            //=======================================
            Pen _penRed = new Pen(Color.Red, 5);
            Rectangle[] _rect = new Rectangle[5];
            int _left = 10;
            int _width = 10;
            int _space = 10;
            int _level = 250;

            for( int index = 0; index < _rect.Length; index++)
            {
                _rect[index] = new Rectangle();
                _rect[index].X = _left + index * ( _width + _space);
                _rect[index].Y = _level - 15 * index;
                _rect[index].Width = _width;
                _rect[index].Height =  15 * index;
            }
            _gpG.FillRectangles( _brush, _rect);

            _gpG.DrawLine( _penRed,_left,_level,250,_level);

            //======================================
            _bmImage.Save( Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion

        //填充椭圆
        FillEllipse#region FillEllipse
        private void FillEllipse()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            //===================
            SolidBrush _brush = new SolidBrush( Color.Black );
            _gpG.FillEllipse( _brush,10,20,100,75);
            //====================
            _bmImage.Save( Response.OutputStream,System.Drawing.Imaging.ImageFormat.Gif);
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion

        //填充扇形
        FillPie#region FillPie
        private void FillPie()
        {
            Bitmap _bmImage = new Bitmap(300,300);
            Graphics _gpG = Graphics.FromImage( _bmImage );
            _gpG.Clear( Color.Wheat );
            SolidBrush _brush = new SolidBrush( Color.Black );
            //=================================
            Rectangle _rect = new Rectangle(10,10,150,150);
            _gpG.FillPie(_brush, _rect,0,270);
            //=================================
            _bmImage.Save( Response.OutputStream, System.Drawing.Imaging.ImageFormat.Gif );
            _bmImage.Dispose();
            _gpG.Dispose();
        }
        #endregion