1         /// <summary>
 2         /// 绘制柱状图
 3         /// </summary>
 4         /// <param name="ds">DataTable中第一列为数据列，第二列为对应的名称</param>
 5         /// <param name="xName">X轴名称</param>
 6         /// <param name="yName">Y轴名称</param>
 7         /// <returns>位图对象</returns>
 8         public Bitmap GetDrawRectangleForStat(DataSet ds, string xName, string yName)
 9         {
10             Bitmap cBmp = new Bitmap(471, 367);  //创建画布宽度为471，高度为367的Bitmap实例
11             Graphics cGraphic;
12             Color[] cColor = new Color[] { Color.Red, Color.Blue, Color.Green, Color.Gray, Color.LightCoral, Color.Gold, Color.Brown, Color.Cyan, Color.Lime, Color.Peru, Color.Magenta, Color.Sienna, Color.Chocolate, Color.PeachPuff, Color.Orange, Color.DarkGoldenrod, Color.Olive, Color.DarkSeaGreen, Color.SpringGreen, Color.Teal, Color.CadetBlue, Color.RoyalBlue, Color.DeepPink, Color.LightGray, Color.MediumVioletRed, Color.Orchid, Color.MediumSlateBlue, Color.White, Color.LightSteelBlue, Color.DarkSlateGray, Color.GreenYellow, Color.DarkKhaki, Color.RosyBrown, Color.Navy, Color.Indigo, Color.HotPink };  //36种颜色
13 
14             Pen cPen;
15             SolidBrush cSolidBrush;
16             Font bFont = new Font("Tahoma", 14, FontStyle.Bold);  //轴标字体
17             Font sFont = new Font("Tahoma", 14, FontStyle.Bold);  //统计数值字体
18             Font fFont = new Font("Tahoma", 14, FontStyle.Bold);  //统计项值字体
19 
20             StringFormat cFormat = new StringFormat();
21             RectangleF cRect;
22             int RowNum = 0;
23             int iLoop = 0;
24             int i = 0;
25             int cValue = 0;
26             int MaxValue = 0;
27 
28             //定义Y轴，Y上(42,15)～Y下(42,317)，Y轴长从17到317共300
29             int xPu = 42;  //Y轴上(Up)点X坐标
30             int yPu = 15;  //Y轴上(Up)点Y坐标
31             int xPd = 42;  //Y轴下(Down)点X坐标
32             int yPd = 317;  //Y轴下(Down)点Y坐标
33 
34             //定义X轴，X左(42,317)～X右(448,317)，X轴上从42到448共406
35             int xPl = 42;  //X轴左(Left)点X坐标
36             int yPl = 317;  //X轴左(Left)点Y坐标
37             int xPr = 448;  //X轴右(Right)点X坐标
38             int yPr = 317;  //X轴右(Right)点Y坐标
39 
40             //定义柱图
41             //int xStart = 57;  //首根柱图开始的X轴坐标
42             //int cWidth = 20;  //柱图宽度
43             //int cSpace = 15;  //柱图间距
44             int xStart = 67;  //首根柱图开始的X轴坐标
45             int cWidth = 40;  //柱图宽度
46             int cSpace = 25;  //柱图间距
47 
48             cGraphic = Graphics.FromImage(cBmp);
49             cGraphic.Clear(Color.Snow);
50 
51             //画轴线
52             cPen = new Pen(Color.Black, 3);
53             cSolidBrush = new SolidBrush(Color.Black);
54             cGraphic.DrawLine(cPen, xPu, yPu, xPd, yPd);  //Y轴
55             cGraphic.DrawLine(cPen, xPl, yPl, xPr, yPr);  //X轴
56 
57             //画轴向
58             cGraphic.DrawLine(cPen, xPu, yPu - 3, xPu - 4, yPu + 3);   //Y轴向
59             cGraphic.DrawLine(cPen, xPu, yPu - 3, xPu + 4, yPu + 3);
60             cGraphic.DrawLine(cPen, xPr + 3, yPr, xPr - 4, yPr - 3);  //X轴向
61             cGraphic.DrawLine(cPen, xPr + 3, yPr, xPr - 4, yPr + 3);
62 
63             //画轴标
64             cFormat.FormatFlags = StringFormatFlags.NoClip;
65             cGraphic.DrawString(yName, bFont, cSolidBrush, 5, 45, cFormat);   //Y轴标
66             cGraphic.DrawString(xName, bFont, cSolidBrush, 392, 332, cFormat);  //X轴标
67 
68             //画轴心值
69             cGraphic.DrawString("0", sFont, cSolidBrush, xPd - 5, yPd + 3, cFormat);
70 
71             RowNum = ds.Tables[0].Rows.Count - 1;
72 
73             for (i = 0; i <= RowNum; i++)
74             {
75                 if (MaxValue < Int32.Parse(ds.Tables[0].Rows[i][0].ToString()))
76                 {
77                     MaxValue = Int32.Parse(ds.Tables[0].Rows[i][0].ToString());
78                 }
79 
80                 //画柱图
81                 cPen = new Pen(cColor[i], 3);
82                 cSolidBrush = new SolidBrush(cColor[i]);
83                 cValue = Int32.Parse(ds.Tables[0].Rows[i][0].ToString()) * ((yPd - yPu) / MaxValue);
84                 cGraphic.DrawRectangle(cPen, xStart + (cWidth + cSpace) * iLoop, yPd - cValue, cWidth, cValue - 2);  //减2的目的：使柱图的下边沿不挡住X轴
85                 cGraphic.FillRectangle(cSolidBrush, xStart + (cWidth + cSpace) * iLoop, yPd - cValue, cWidth, cValue - 2);
86 
87                 //画柱图统计Y轴值
88                 cGraphic.DrawString(ds.Tables[0].Rows[i][0].ToString(), sFont, cSolidBrush, xStart + (cWidth + cSpace) * iLoop - 2, yPd - cValue - 20, cFormat);
89 
90                 //画柱图统计X轴值
91                 cRect = new RectangleF(xStart + (cWidth + cSpace) * iLoop, yPd + 1, cWidth + 10, 40);
92                 cGraphic.DrawString(ds.Tables[0].Rows[i][1].ToString(), fFont, cSolidBrush, cRect, cFormat);
93 
94                 iLoop += 1;
95             }
96 
97             return cBmp;
98         }