C# 利用MSChart控件

我有一个简单的线条图，我想通过在线条周围画一个矩形（理想情况下是一个透明的填充矩形…）来突出显示这个图形的一些部分。我不知道MS图表控件是否可以实现这一点？

您的意思是：

using (Graphics g = Graphics.FromImage(pictureBox1.Image))
{
    using(Brush brush = new SolidBrush(your_color))
    {
        g.FillRectangle(brush , x, y, width, height);
    }
}

或者你可以使用

Brush brush = new SolidBrush(Color.FromArgb(alpha, red, green, blue))

---

其中

alpha

从0变为255，因此

alpha

的128值将提供50%不透明度。

我建议您下载并查看注释部分。在这里，您将找到实现所述目标所需的所有文档：

private void AddRectangleAnnotation()
{
RectangleAnnotation annotation = new RectangleAnnotation();
annotation.AnchorDataPoint = Chart1.Series[0].Points[2];
annotation.Text = "I am a\nRectangleAnnotation";
annotation.ForeColor = Color.Black;
annotation.Font = new Font("Arial", 12);;
annotation.LineWidth = 2;
annotation.BackColor = Color.PaleYellow;
annotation.LineDashStyle = ChartDashStyle.Dash;

Chart1.Annotations.Add(annotation);
}

---

当你想在图表上画图时，你可以选择添加线性注释或矩形注释。如果你想要更多的控制，你可以使用图表的前画和后画事件。如果你能画画，那么你可以画任何东西。此外，使用此选项将使图表“打印”和“导出”看起来与绘制时相同。当图表在屏幕上的位置发生变化时，在上面涂鸦看起来会很有趣，所以一定要在上面画画

假设你有一张交易图表，你需要画一条线来说明你在哪里盈利，或者说你在哪里“做什么”，然后加上你想去的地方和你想去的地方的坐标

显示如何使用以下代码执行此操作（也可使用vb.net）：

---

我的意思是使用控件System.Windows.Forms.DataVisualization.Charting.Chart并覆盖一个矩形。使用控件的后期事件。太棒了！您现在有没有办法偏移矩形，以使左下角成为定位点？最后，我没有使用AnchorOffset属性，因为行为是不连贯的（设置x偏移也会导致y偏移…？？）。相反，我使用X和Y属性设置了位置，但没有锚定，这在我的例子中不是问题。您现在有没有办法偏移矩形，以使左下角成为锚定点我想你可以设定一个负八来实现这一点。

using System.Windows.Forms.DataVisualization.Charting;
...

private void chart1_PostPaint(object sender, System.Windows.Forms.DataVisualization.Charting.ChartPaintEventArgs e)
{
    if(sender is ChartArea)
    {

        ChartArea area = (ChartArea)sender;
        if(area.Name == "Default")
        {
            // If Connection line is not checked return
            if( !ConnectionLine.Checked )
                return;

            double max;
            double min;
            double xMax;
            double xMin;

            // Find Minimum and Maximum values
            FindMaxMin( out max, out min, out xMax, out xMin );

            // Get Graphics object from chart
            Graphics graph = e.ChartGraphics.Graphics;

            // Convert X and Y values to screen position
            float pixelYMax = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.Y,max);
            float pixelXMax = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.X,xMax);
            float pixelYMin = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.Y,min);
            float pixelXMin = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.X,xMin);

            PointF point1 = PointF.Empty;
            PointF point2 = 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);
        }
    }
}

private void chart1_PrePaint(object sender, System.Windows.Forms.DataVisualization.Charting.ChartPaintEventArgs e)
{
    if(sender is ChartArea){

        ChartArea area = (ChartArea)sender;
        if(area.Name == "Default")
        {
            double max;
            double min;
            double xMax;
            double xMin;

            // Find Minimum and Maximum values
            FindMaxMin( out max, out min, out xMax, out xMin );

            // Get Graphics object from chart
            Graphics graph = e.ChartGraphics.Graphics;

            // Convert X and Y values to screen position
            float pixelYMax = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.Y,max);
            float pixelXMax = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.X,xMax);
            float pixelYMin = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.Y,min);
            float pixelXMin = (float)e.ChartGraphics.GetPositionFromAxis("Default",AxisName.X,xMin);

            // Specify width of triangle
            float width = 3;

            // Set Maximum points
            PointF [] points = new PointF[3];
            points[0].X = pixelXMax - width;
            points[0].Y = pixelYMax - width - 2;
            points[1].X = pixelXMax + width;
            points[1].Y = pixelYMax - width - 2;
            points[2].X = pixelXMax;
            points[2].Y = pixelYMax - 1;

            // Convert relative coordinates to absolute coordinates.
            points[0] = e.ChartGraphics.GetAbsolutePoint(points[0]);
            points[1] = e.ChartGraphics.GetAbsolutePoint(points[1]);
            points[2] = e.ChartGraphics.GetAbsolutePoint(points[2]);

            // Draw Maximum trangle
            graph.FillPolygon(new SolidBrush(Color.Red), points);

            // Set Minimum points
            points = new PointF[3];
            points[0].X = pixelXMin - width;
            points[0].Y = pixelYMin + width + 2;
            points[1].X = pixelXMin + width;
            points[1].Y = pixelYMin + width + 2;
            points[2].X = pixelXMin;
            points[2].Y = pixelYMin + 1;

            // Convert relative coordinates to absolute coordinates.
            points[0] = e.ChartGraphics.GetAbsolutePoint(points[0]);
            points[1] = e.ChartGraphics.GetAbsolutePoint(points[1]);
            points[2] = e.ChartGraphics.GetAbsolutePoint(points[2]);

            // Draw Minimum triangle
            graph.FillPolygon(new SolidBrush(Color.Blue), points);
        }
    }
}