mschart怎末画横线？

[xiaoyu48431]

请问怎么在mschart中画水平线
因为图中需要标明上下阈值
这样很容易看出那个月的数值不符合要求

[loveseunghun]

多设一个 series，然后y坐标设成固定值，这样不行吗？

[xiaoyu48431]

好了 解决了
就是又画了一个series

缺点就是直线无法从纵轴开始延伸

[loveseunghun]

好像还有这个方法
StripLine sl1 = new StripLine();
sl1.BackColor = System.Drawing.Color.Red;
sl1.IntervalOffset = 1;
sl1.StripWidth = 0.001;
sl1.StripWidthType = DateTimeIntervalType.Number;
sl1.Text = "上限";
sl1.TextAlignment = StringAlignment.Near;
ChartLine1.ChartAreas[0].AxisY.StripLines.Add(sl1);

我试了，挺管用的

[cupwei]

3楼的设置一个上限是管用的 但是不能动态的改变啊

[夜归人]

可以用线状的Annotation画一天横线，调整Annotation坐标

[VeryShooter]

图形化方法：
右击MSChart---属性---ChartAreas---Axes---Y (Value) axis---StripLines---添加一个StripLine---设置IntervalOffSet属性值（距离Y轴远点的距离，也就是阈值），BackColor的颜色（默认是白色，看不见，改成别的显眼的颜色）。

编程方法：（见http://blog.csdn.net/loveseunghun/article/details/5554626）
StripLine sl1 = new StripLine();
sl1.BackColor = System.Drawing.Color.Red; //默认为白色，看不见
sl1.IntervalOffset = 1;
sl1.StripWidth = 0.001;
sl1.Text = "上限";
sl1.TextAlignment = StringAlignment.Near;
ChartLine1.ChartAreas[0].AxisY.StripLines.Add(sl1);
StripLine sl1 = new StripLine();
sl1.BackColor = System.Drawing.Color.Red;
sl1.IntervalOffset = 1;
sl1.StripWidth = 0.001;
sl1.Text = "上限";
sl1.TextAlignment = StringAlignment.Near;
ChartLine1.ChartAreas[0].AxisY.StripLines.Add(sl1);

[tigertang123]

MSChart 实例里面画线的 实例代码

Private Sub Chart1_PostPaint(sender As Object, e As System.Windows.Forms.DataVisualization.Charting.ChartPaintEventArgs) Handles Chart1.PostPaint
   If TypeOf sender Is ChartArea Then
      
      Dim area As ChartArea = CType(sender, ChartArea)
      If area.Name = "Default" Then
         ' If Connection line is not checked return
         If Not ConnectionLine.Checked Then
            Return
         End If 
         Dim max As Double
         Dim min As Double
         Dim xMax As Double
         Dim xMin As Double
         
         ' Find Minimum and Maximum values
         FindMaxMin(max, min, xMax, xMin)
         
         ' Get Graphics object from chart
         Dim graph As Graphics = e.ChartGraphics.Graphics
         
         ' Convert X and Y values to screen position
         Dim pixelYMax As Single = CSng(e.ChartGraphics.GetPositionFromAxis("Default", AxisName.Y, max))
         Dim pixelXMax As Single = CSng(e.ChartGraphics.GetPositionFromAxis("Default", AxisName.X, xMax))
         Dim pixelYMin As Single = CSng(e.ChartGraphics.GetPositionFromAxis("Default", AxisName.Y, min))
         Dim pixelXMin As Single = CSng(e.ChartGraphics.GetPositionFromAxis("Default", AxisName.X, xMin))
         
         Dim point1 As PointF = PointF.Empty
         Dim point2 As PointF = PointF.Empty
         
         ' Set Maximum and minimum points
         point1.X = pixelXMax
         point1.Y = pixelYMax
         point2.X = pixelXMin
         point2.Y = pixelYMin
         
         ' Convert relative coordinates to absolute coordinates.
         point1 = e.ChartGraphics.GetAbsolutePoint(point1)
         point2 = e.ChartGraphics.GetAbsolutePoint(point2)
         
         ' Draw connection line
         graph.DrawLine(New Pen(Color.Yellow, 3), point1, point2)
      End If
   End If
End Sub