C#饼状图和柱状图

当我们的软件需要各种饼状图和柱状图来表示数据时，我们或许会想到用Offices中的图形控件或是第三方控件，但现在的第三方控件大都需要注册，有些免费的控件会有开发商的标记等。而对于使用Offices的图形控件来说，并不能在程序中得于很好控制，其使用的简易程度也较低，所以在这我给出在C#中使用GDI+实现饼状图和柱状图跟数据库联接显示数据的方法。 using System; using System.IO;//用于文件存取 using System.Data;//用于数据访问 using System.Drawing;//提供画GDI+图形的基本功能 using System.Drawing.Text;//提供画GDI+图形的高级功能 using System.Drawing.Drawing2D;//提供画高级二维，矢量图形功能 using System.Drawing.Imaging;//提供画GDI+图形的高级功能 namespace BaseLayer { public class PieChart { public PieChart() { } //Render是图形大标题，图开小标题，图形宽度，图形长度，饼图的数据集和饼图的数据集要表示出来的数据 public Image Render(string title, string subTitle, int width, int height, DataSet chartData,int DataLine) { const int SIDE_LENGTH = 400; const int PIE_DIAMETER = 200; DataTable dt = chartData.Tables[0]; //通过输入参数，取得饼图中的总基数 float sumData = 0; foreach(DataRow dr in dt.Rows) { sumData += Convert.ToSingle(dr[DataLine]); } //产生一个image对象，并由此产生一个Graphics对象 Bitmap bm = new Bitmap(width,height); Graphics g = Graphics.FromImage(bm); //设置对象g的属性 g.ScaleTransform((Convert.ToSingle(width))/SIDE_LENGTH,(Convert.ToSingle(height))/SIDE_LENGTH); g.SmoothingMode = SmoothingMode.Default; g.TextRenderingHint = TextRenderingHint.AntiAlias; //画布和边的设定 g.Clear(Color.White); g.DrawRectangle(Pens.Black,0,0,SIDE_LENGTH-1,SIDE_LENGTH-1); //画饼图标题 g.DrawString(title,new Font(Tahoma,14),Brushes.Black,new PointF(5,5)); //画饼图的图例 g.DrawString(subTitle,new Font(Tahoma,12),Brushes.Black,new PointF(7,35)); //画饼图 float curAngle = 0; float totalAngle = 0; for(int i=0;i<dt.Rows.Count;i++) { curAngle = Convert.ToSingle(dt.Rows[i][DataLine]) / sumData * 360; g.FillPie(new SolidBrush(ChartUtil.GetChartItemColor(i)),100,65,PIE_DIAMETER,PIE_DIAMETER,totalAngle,curAngle); g.DrawPie(Pens.Black,100,65,PIE_DIAMETER,PIE_DIAMETER,totalAngle,curAngle); totalAngle += curAngle; } //画图例框及其文字 g.DrawRectangle(Pens.Black,200,300,199,99); g.DrawString(图表说明,new Font(Tahoma,12,FontStyle.Bold),Brushes.Black,new PointF(200,300)); //画图例各项 PointF boxOrigin = new PointF(210,330); PointF textOrigin = new PointF(235,326); float percent = 0; for(int i=0;i<dt.Rows.Count;i++) { g.FillRectangle(new SolidBrush(ChartUtil.GetChartItemColor(i)),boxOrigin.X,boxOrigin.Y,20,10); g.DrawRectangle(Pens.Black,boxOrigin.X,boxOrigin.Y,20,10); percent = Convert.ToSingle(dt.Rows[i][DataLine]) / sumData * 100; g.DrawString(dt.Rows[i][1].ToString() + - + dt.Rows[i][0].ToString() + ( + percent.ToString(0) + %),new Font(Tahoma,10),Brushes.Black,textOrigin); boxOrigin.Y += 15; textOrigin.Y += 15; } //回收资源 g.Dispose(); return (Image) bm; } }

//画条形图 public class BarChart { public BarChart() { } //Render是图形大标题，图开小标题，图形宽度，图形长度，饼图的数据集和饼图的数据集 public Image Render(string title, string subTitle, int width, int height, DataSet chartData) { const int SIDE_LENGTH = 400; const int CHART_TOP = 75; const int CHART_HEIGHT = 200; const int CHART_LEFT = 50; const int CHART_WIDTH = 300; DataTable dt = chartData.Tables[0]; //计算最高的点 float highPoint = 0; foreach(DataRow dr in dt.Rows) { if(highPoint<Convert.ToSingle(dr[0])) { highPoint = Convert.ToSingle(dr[0]); } } //建立一个Graphics对象实例 Bitmap bm = new Bitmap(width,height); try { Graphics g = Graphics.FromImage(bm); //设置条图图形和文字属性 g.ScaleTransform((Convert.ToSingle(width))/SIDE_LENGTH,(Convert.ToSingle(height))/SIDE_LENGTH); g.SmoothingMode = SmoothingMode.Default; g.TextRenderingHint = TextRenderingHint.AntiAlias; //设定画布和边 g.Clear(Color.White); g.DrawRectangle(Pens.Black,0,0,SIDE_LENGTH-1,SIDE_LENGTH-1); //画大标题 g.DrawString(title,new Font(Tahoma,14),Brushes.Black,new PointF(5,5)); //画小标题 g.DrawString(subTitle,new Font(Tahoma,12),Brushes.Black,new PointF(7,35)); //画条形图 float barWidth = CHART_WIDTH / (dt.Rows.Count * 2); PointF barOrigin = new PointF(CHART_LEFT + (barWidth / 2),0); float barHeight = dt.Rows.Count; for(int i=0;i<dt.Rows.Count;i++) { barHeight = Convert.ToSingle(dt.Rows[i][0]) * 200 / highPoint * 1; barOrigin.Y = CHART_TOP + CHART_HEIGHT - barHeight; g.FillRectangle(new SolidBrush(ChartUtil.GetChartItemColor(i)),barOrigin.X,barOrigin.Y,barWidth,barHeight); barOrigin.X = barOrigin.X + (barWidth * 2); } //设置边 g.DrawLine(new Pen(Color.Black,2),new Point(CHART_LEFT,CHART_TOP),new Point(CHART_LEFT,CHART_TOP + CHART_HEIGHT)); g.DrawLine(new Pen(Color.Black,2),new Point(CHART_LEFT,CHART_TOP + CHART_HEIGHT),new Point(CHART_LEFT + CHART_WIDTH,CHART_TOP + CHART_HEIGHT)); //画图例框和文字 g.DrawRectangle(new Pen(Color.Black,1),200,300,199,99); g.DrawString(图表说明,new Font(Tahoma,12,FontStyle.Bold),Brushes.Black,new PointF(200,300)); //画图例 PointF boxOrigin = new PointF(210,330); PointF textOrigin = new PointF(235,326); for(int i=0;i<dt.Rows.Count;i++) { g.FillRectangle(new SolidBrush(ChartUtil.GetChartItemColor(i)),boxOrigin.X,boxOrigin.Y,20,10); g.DrawRectangle(Pens.Black,boxOrigin.X,boxOrigin.Y,20,10); g.DrawString(dt.Rows[i][1].ToString() + - + dt.Rows[i][0].ToString(),new Font(Tahoma,10),Brushes.Black,textOrigin); boxOrigin.Y += 15; textOrigin.Y += 15; } //输出图形 g.Dispose(); return bm; } catch { return bm; } } } public class ChartUtil { public ChartUtil() { } public static Color GetChartItemColor(int itemIndex) { Color selectedColor; switch(itemIndex) { case 0: selectedColor = Color.Blue; break; case 1: selectedColor = Color.Red; break; case 2: selectedColor = Color.Yellow; break; case 3: selectedColor = Color.Purple; break; default: selectedColor = Color.Green; break; } return selectedColor; } } }