浅谈C#使用GDI+

C#使用GDI+

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#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<i style="color:transparent">本文来源gaodai$ma#com搞$$代**码网$</i> 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);  barOriginbarOrigin.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。C#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。

更多浅谈C#使用GDI+相关文章请关注搞代码！

喜欢 (0)赏

[搞代码]

分享 (0)