asp.net生成数据饼图/柱状图

1.Page_load事件

Bitmap objBitMap = new Bitmap(400, 200);
   Graphics objGraphics;
   objGraphics = Graphics.FromImage(objBitMap);
   objGraphics.Clear(Color.White);
   int[] arrValues = {100,135,115,125,75,120};
   string[] arrValueNames = new string[]{"一月","二月","三月","四月","五月","六月"};
   objGraphics.DrawString(" X 公司上半年销售情况",
   new Font("宋体", 16), Brushes.Black, new PointF(5, 5));
   PointF symbolLeg = new PointF(335, 20);
   PointF descLeg = new PointF(360, 16);
   for (int i = 0; i < arrValueNames.Length; i++)
   {
   objGraphics.FillRectangle(new SolidBrush(GetColor(i)), symbolLeg.X, symbolLeg.Y, 20, 10);
   objGraphics.DrawRectangle(Pens.Black, symbolLeg.X, symbolLeg.Y, 20, 10);
   objGraphics.DrawString(arrValueNames[i].ToString(), new Font("宋体", 10), Brushes.Black, descLeg);
   symbolLeg.Y += 15;
   descLeg.Y += 15;
   }
   for (int i = 0; i < arrValues.Length; i++)
   {
   objGraphics.FillRectangle(new SolidBrush(GetColor(i)), (i * 35) + 15, 200 - arrValues[i], 20,
   arrValues[i] + 5);
   objGraphics.DrawRectangle(Pens.Black, (i * 35) + 15, 200 - arrValues[i], 20, arrValues[i] + 5);
   }
   float sglCurrentAngle = 0;
   float sglTotalAngle = 0;
   float sglTotalValues = 0;
   for (int i = 0; i <= arrValues.Length - 1; i++)
   {
   sglTotalValues += arrValues[i];
   }
   for (int i = 0; i < arrValues.Length; i++)
   {
   sglCurrentAngle = arrValues[i] / sglTotalValues * 360;
   objGraphics.FillPie(new SolidBrush(GetColor(i)), 220, 95, 100, 100, sglTotalAngle, sglCurrentAngle);
   objGraphics.DrawPie(Pens.Black, 220, 95, 100, 100, sglTotalAngle, sglCurrentAngle);
   sglTotalAngle += sglCurrentAngle;
   }
   objBitMap.Save(Response.OutputStream, ImageFormat.Gif);

2.GetColor()函数

private Color GetColor(int itemIndex)
  {
   Color objColor;
   if (itemIndex == 0)
   {
   objColor = Color.Blue;
   }
   else if (itemIndex == 1)
   {
   objColor = Color.Red;
   }
   else if (itemIndex == 2)
   {
   objColor = Color.Yellow;
   }
   else if (itemIndex == 3)
   {
   objColor = Color.Purple;
   }
   else if (itemIndex == 4)
   {
   objColor = Color.Orange;
   }
   else if (itemIndex == 5)
   {
   objColor = Color.Brown;
   }
   else if (itemIndex == 6)
   {
   objColor = Color.Gray;
   }
   else if (itemIndex == 7)
   {
   objColor = Color.Maroon;
   }
   else if (itemIndex == 8)
   {
   objColor = Color.Maroon;
   }
   else
   {
   objColor = Color.Blue;
   }
   return objColor;
  }

3.加入命名空间:
using System.Drawing.Imaging;

4.效果图如下: