什么是十字准线光标？
一条十字准线光标是在窗体上简单的呈现水平和竖直交叉线。
它的相互点定义鼠标和值。
在图表上十字准线光标的需求
十字准线光标在图表上市基础功能之一，它能在图表上展示一定范围内的数据。有了这个数据，就能精确的衡量图表。
然而，绘制十字准线光标需要准确的位置，比如数据点的X和Y值。
图表十字准线的交互
图表上有两组。绘制图表一般只使用Group0，而留着Group1不用。然而Group1有其他的用途，比如展示动态图表，根据鼠标的移动而移动，它的绘制方式就是十字准线。
有两件基本的事情需要考虑完成：
绘制十字准线实现的Group0数据
绘制图表的Group0包括给Chart添加序列，绘制X和Y值。
1: //Add Series
2: c1Chart1.ChartGroups[1].ChartData.SeriesList.AddNewSeries();
3: c1Chart1.ChartGroups[1].ChartData.SeriesList.AddNewSeries();
4: c1Chart1.ChartGroups[1].ChartData.SeriesList.AddNewSeries();
5: c1Chart1.ChartGroups[1].ChartData.SeriesList.AddNewSeries();
6: c1Chart1.ChartGroups[1].ChartData.SeriesList.AddNewSeries();
7:
8: //Populate X Values
9: c1Chart1.ChartGroups[1].ChartData.SeriesList[0].AutoEnumerate = true;
10: c1Chart1.ChartGroups[1].ChartData.SeriesList[1].AutoEnumerate = true;
11: c1Chart1.ChartGroups[1].ChartData.SeriesList[2].AutoEnumerate = true;
12: c1Chart1.ChartGroups[1].ChartData.SeriesList[3].AutoEnumerate = true;
13: c1Chart1.ChartGroups[1].ChartData.SeriesList[4].AutoEnumerate = true;
14:
15: //Populate Y Values
16: c1Chart1.ChartGroups[1].ChartData.SeriesList[0].Y.CopyDataIn(new double[] { 12, 19, 15, 31, 44, 17 });
17: c1Chart1.ChartGroups[1].ChartData.SeriesList[1].Y.CopyDataIn(new double[] { 22, 14, 27, 35, 51, 22 });
18: c1Chart1.ChartGroups[1].ChartData.SeriesList[2].Y.CopyDataIn(new double[] { 16, 17, 22, 33, 20, 33 });
19: c1Chart1.ChartGroups[1].ChartData.SeriesList[3].Y.CopyDataIn(new double[] { 21, 12, 13, 16, 17, 51 });
20: c1Chart1.ChartGroups[1].ChartData.SeriesList[4].Y.CopyDataIn(new double[] { 11, 41, 25, 13, 24, 11 });
在展示十字准线中绘制动态线
通过MouseMove事件用来在Group1绘制动态线.
当鼠标移动的时候，图表的数据Group1会被清除和重新计算。这个数据是和鼠标值同步的。
1: void c1Chart1_MouseMove(object sender, MouseEventArgs e)
2: {
3: x = e.X;
4: y = e.Y;
5: float X = 0f, Y = 0f;
6:
7: //Add series
8: c1Chart1.ChartGroups[0].ChartData.SeriesList.Clear();
9: c1Chart1.ChartGroups[0].ChartData.SeriesList.AddNewSeries();
10: c1Chart1.ChartGroups[0].ChartData.SeriesList.AddNewSeries();
11:
12: //Populate the series with X and Y Values
13: c1Chart1.ChartGroups[0].CoordToDataCoord(x, y, ref X, ref Y);
14: double[] xSerHorz = new double[3] { (double)c1Chart1.ChartArea.AxisX.Min, (double)X, (double)c1Chart1.ChartArea.AxisX.Max };
15: double[] ySerHorz = new double[3] { (double)Y, (double)Y, (double)Y };
16: double[] xSerVert = new double[3] { (double)X, (double)X, (double)X };
17: double[] ySerVert = new double[3] { (double)c1Chart1.ChartArea.AxisY.Min, (double)Y, (double)c1Chart1.ChartArea.AxisY.Max };
18: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].X.CopyDataIn(xSerHorz);
19: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].Y.CopyDataIn(ySerHorz);
20: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].X.CopyDataIn(xSerVert);
21: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].Y.CopyDataIn(ySerVert);
22:
23: //Style the Series
24: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].SymbolStyle.Shape = C1.Win.C1Chart.SymbolShapeEnum.DiagCross;
25: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].SymbolStyle.Color = Color.Orange;
26: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].SymbolStyle.OutlineColor = Color.Orange;
27: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].SymbolStyle.Size = 3;
28: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].LineStyle.Color = Color.Red;
29: c1Chart1.ChartGroups[0].ChartData.SeriesList[0].LineStyle.Thickness = 2;
30:
31: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].SymbolStyle.Shape = C1.Win.C1Chart.SymbolShapeEnum.DiagCross;
32: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].SymbolStyle.Color = Color.Orange;
33: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].SymbolStyle.OutlineColor = Color.Orange;
34: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].SymbolStyle.Size = 3;
35: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].LineStyle.Color = Color.Red;
36: c1Chart1.ChartGroups[0].ChartData.SeriesList[1].LineStyle.Thickness = 2;
37:
38: c1Chart1.ToolTip.Enabled = true;
39: c1Chart1.Visible = true;
40:
41: //Attach a Chart Label with the Coordinate to display the value of the point under the cross-hair cursor
42: c1Chart1.ChartLabels.LabelsCollection.AddNewLabel();
43: c1Chart1.ChartLabels.LabelsCollection[0].AttachMethod = C1.Win.C1Chart.AttachMethodEnum.Coordinate;
44: c1Chart1.ChartLabels.LabelsCollection[0].AttachMethodData.X = x;
45: c1Chart1.ChartLabels.LabelsCollection[0].AttachMethodData.Y = y - 8;
46: c1Chart1.ChartLabels.LabelsCollection[0].Text = "X= " + X.ToString() + ", Y= " + Y.ToString();
47: c1Chart1.ChartLabels.LabelsCollection[0].Visible = true;
48: c1Chart1.ChartLabels.DefaultLabelStyle.BackColor = Color.Red;
49:
50: }
因此就可以在图表中展示十字准线。
本文的示例参考：
资源
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