如何在C#的WinForm中制作饼状图和柱状图_c# 圆饼

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; 
} 
} 
} 
以上是一个完整的WinForm中制作饼状图和柱状图源程序，大家可以通过以上程序的更改，做出能满足自己程序的需要。