實現思路為，在該窗體上添加一個lable標簽，當鼠標經過折線點時獲取該點的x軸，y軸值和鼠標坐標值。然后將lable的坐標標記為鼠標所在坐標，并且給lable賦值，并且將lable顯示出來。
具體實現代碼如下：
/// <summary>
/// 鼠標移動到曲線圖上顯示值
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void chart4_MouseMove(object sender, MouseEventArgs e)
{
var chart = sender as Chart;
if (chart != null)
{
HitTestInfo hit = chart.HitTest(e.X, e.Y);
var o = hit.Object as Element;
if (o != null)
{
var yvaule = o.YValue;
label2.Visible = true;//鼠標經過時label顯示
label2.Text = yvaule.ToString(CultureInfo.InvariantCulture);
label2.Location = new Point(e.X, e.Y - 20);
}
else//鼠標離開時lable隱藏
{
label2.Visible = false;
}
}
}
