c#代码画图

说明：此示例代码在我做的一个项目中  不过还是可以学习一下

一：直角坐标系显示数据

先看效果图：

代码：

        private List<int> Conuts = new List<int>();

        public List<int> Conuts1
        {
            get { return Conuts; }
            set { Conuts = value; }
        }
        protected void Page_Load(object sender, EventArgs e)
        {

            StaffSystemDataContext dc = new StaffSystemDataContext();
            var Deps = dc.PropertyMappings.Where(p => p.PropertyName.Equals("DepartmentID"));
            foreach (var dep in Deps)
            {
                var Pros = dc.Projects.Where(p => p.DepartmentID.Equals(dep.PropertyValue));
                Conuts1.Add(Pros.Count());
            }
            //画图初始化
            Bitmap bMap = new Bitmap(500, 500);
            Graphics gph = Graphics.FromImage(bMap);
            gph.Clear(Color.White);
            //中心点
            PointF cPt = new PointF(40, 420);
            //X轴三角形
            PointF[] xPt = new PointF[3] { new PointF(cPt.Y + 15, cPt.Y), new PointF(cPt.Y, cPt.Y - 8), new PointF(cPt.Y, cPt.Y + 8) };
            //Y轴三角形
            PointF[] yPt = new PointF[3] { new PointF(cPt.X, cPt.X - 15), new PointF(cPt.X - 8, cPt.X), new PointF(cPt.X + 8, cPt.X) };
            //图表标题
            gph.DrawString("部门项目汇总图表", new Font("宋体", 14), Brushes.Black, new PointF(cPt.X + 60, cPt.X));
            //画X轴
            gph.DrawLine(Pens.Black, cPt.X, cPt.Y, cPt.Y, cPt.Y);
            gph.DrawPolygon(Pens.Black, xPt);
            gph.FillPolygon(new SolidBrush(Color.Black), xPt);
            gph.DrawString("部门", new Font("宋体", 12), Brushes.Black, new PointF(cPt.Y + 10, cPt.Y + 10));
            //画Y轴
            gph.DrawLine(Pens.Black, cPt.X, cPt.Y, cPt.X, cPt.X);
            gph.DrawPolygon(Pens.Black, yPt);
            gph.FillPolygon(new SolidBrush(Color.Black), yPt);
            gph.DrawString("项目数", new Font("宋体", 12), Brushes.Black, new PointF(0, 7));
            //画Y轴刻度
            for (int i = 1; i <= 10; i++)
            {
                gph.DrawString(i.ToString(), new Font("宋体", 11), Brushes.Black, new PointF(cPt.X - 30, cPt.Y - i * 30 - 6));
                gph.DrawLine(Pens.Black, cPt.X - 3, cPt.Y - i * 30, cPt.X, cPt.Y - i * 30);
            }
            //画X轴项目 
            int a = 1;
            foreach (var dep in Deps)
            {

                gph.DrawString(dep.PropertyMeaning.Substring(0, 1), new Font("宋体", 11), Brushes.Black, new PointF(cPt.X + a * 30 - 5, cPt.Y + 5));
                gph.DrawString(dep.PropertyMeaning.Substring(1, 1), new Font("宋体", 11), Brushes.Black, new PointF(cPt.X + a * 30 - 5, cPt.Y + 20));
                gph.DrawString(dep.PropertyMeaning.Substring(2, 1), new Font("宋体", 11), Brushes.Black, new PointF(cPt.X + a * 30 - 5, cPt.Y + 35));
                a++;
            }
            for (int i = 1; i <= Deps.Count(); i++)
            {
                //画点
                gph.DrawEllipse(Pens.Black, cPt.X + i * 30 - 1.5F, cPt.Y - Conuts1[i - 1] * 30 - 1.5F, 3, 3);
                gph.FillEllipse(new SolidBrush(Color.Black), cPt.X + i * 30 - 1.5F, cPt.Y - Conuts1[i - 1] * 30 - 1.5F, 3, 3);
                //画数值
                gph.DrawString(Conuts1[i - 1].ToString(), new Font("宋体", 11), Brushes.Black, new PointF(cPt.X + i * 30, cPt.Y - Conuts1[i - 1] * 30));
                //画折线
                if (i > 1)
                    gph.DrawLine(Pens.Red, cPt.X + (i - 1) * 30, cPt.Y - Conuts1[i - 2] * 30, cPt.X + i * 30, cPt.Y - Conuts1[i - 1] * 30);
            }
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            bMap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
            Response.ClearContent();
            Response.ContentType = "image/Png";
            Response.BinaryWrite(ms.ToArray());
            gph.Dispose();
            bMap.Dispose();
            Response.End();
        }

注意：这里的坐标都是从左上角开始算   而且必须使用最后的一小段代码将其转化为图片

二：绘制圆形效果

 StaffSystemDataContext dc = new StaffSystemDataContext();
            var Deps = dc.PropertyMappings.Where(p => p.PropertyName.Equals("DepartmentID"));

            //创建画图对象
            int width = 800, height = 800;
            Bitmap bitmap = new Bitmap(width, height);
            Graphics g = Graphics.FromImage(bitmap);
            try
            {
                //清空背景色
                g.Clear(Color.White);
                Pen pen1 = new Pen(Color.Red);

                Brush brush1 = new SolidBrush(Color.PowderBlue);
                Brush brush2 = new SolidBrush(Color.Blue);
                Brush brush3 = new SolidBrush(Color.Wheat);
                Brush brush4 = new SolidBrush(Color.Orange);
                Brush brush5 = new SolidBrush(Color.Gray);
                Brush brush6 = new SolidBrush(Color.Red);
                Brush brush7 = new SolidBrush(Color.White);
                Brush[] brs = new Brush[] { brush1, brush2, brush3, brush4, brush5, brush6 };
                Font font1 = new Font("Courier New", 16, FontStyle.Bold);
                Font font2 = new Font("Courier New", 8);
                g.FillRectangle(brush7, 0, 0, width, height);    //绘制背景图
                g.DrawString("员工部门比例饼形图", font1, brush2, new Point(80, 20));  //书写标题
                int piex = 100, piey = 60, piew = 200, pieh = 200, sum = 0;
                var Pros = dc.Projects.Where(p => p.DepartmentID != null);
                sum = Pros.Count();
                int a = 0;
                float j = 0;
                foreach (var dep in Deps)
                {
                    var Prods = dc.Projects.Where(p => p.DepartmentID.Equals(dep.PropertyValue));
                    //计算角度
                    float angle = Convert.ToSingle((360 / Convert.ToSingle(sum)) * Convert.ToSingle(Prods.Count()));
                    //绘制员工所占比例
                    //FieldInfo fi = type.GetField("ddd" + i.ToString());
                    //temp += fi.GetValue(this).ToString();
                    //Type type = this.GetType(); 
                    //Brush fi = (Brush)type.GetField("brush" + a.ToString());
                    g.FillPie(brs[a], piex, piey, piew, pieh, j, angle);
                    a++;
                    j = j + angle;
                }

                //绘制标识
                g.DrawRectangle(pen1, 50, 280, 400, 300);  //绘制范围框
                //绘制小矩形
                int le = 320, b = 0;
                foreach (var dep in Deps)
                {
                    var Prods = dc.Projects.Where(p => p.DepartmentID.Equals(dep.PropertyValue));
                    g.FillRectangle(brs[b], 90, le, 20, 10);
                    g.DrawString("" + dep.PropertyMeaning + "员工占公司总人数比例:" + Convert.ToSingle(Prods.Count()) * 100 / Convert.ToSingle(sum) + "%", font2, brs[b], 120, le);
                    le += 40;
                    b++;
                }
            }
            catch (Exception ex)
            {
                throw new Exception("有错！！！");
            }
            System.IO.MemoryStream ms = new System.IO.MemoryStream();
            bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
            Response.ClearContent();
            Response.ContentType = "image/Png";
            Response.BinaryWrite(ms.ToArray());
            g.Dispose();
            bitmap.Dispose();
            Response.End();