学步园

目标
1、鼠标移到线段上方，该段线段高亮

步骤（在之前代码基础之上）
1、实现chart的mousemove事件，代码如下

private void chart1_MouseMove(object sender, MouseEventArgs e)
{
    // Call HitTest
    HitTestResult result = chart1.HitTest(e.X, e.Y);

    // Reset Data Point Attributes
    foreach (DataPoint point in chart1.Series[0].Points)
    {
        point.BackSecondaryColor = Color.Black;
        point.BackHatchStyle = ChartHatchStyle.None;
        point.BorderWidth = 1;
    }

    // If the mouse if over a data point
    if (result.ChartElementType == ChartElementType.DataPoint)
    {
        // Find selected data point
        DataPoint point = chart1.Series[0].Points[result.PointIndex];

        // Change the appearance of the data point
        point.BackSecondaryColor = Color.White;
        point.BackHatchStyle = ChartHatchStyle.Percent25;
        point.BorderWidth = 2;
    }
    else
    {
        // Set default cursor
        this.Cursor = Cursors.Default;
    }
}

2、效果如下
首先，窗体刚启动，如下

鼠标移动上，效果如下