将鼠标悬停在折线图上时显示工具提示

本文关键字：显示 工具提示 折线图 鼠标 悬停 | 更新日期: 2023-09-27 18:25:04

有人能帮我检查代码吗？当我的鼠标悬停在折线图上时，它不会弹出工具提示来显示信息。有什么问题吗？非常感谢。

我的想法是，当鼠标沿着折线图移动时，它会弹出一个提示来shpw x轴值和y轴值，但当我的鼠标悬停在折线图上时，不会弹出任何内容。这是我的代码，我从其他地方复制的鼠标悬停事件：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Windows.Forms.DataVisualization.Charting;

namespace Project42
{
    public partial class Form1 : Form
    {
        static class Program
        {
            /// <summary>
            /// The main entry point for the application.
            /// </summary>
            [STAThread]
            static void Main()
            {
                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);
                Application.Run(new Form1());
            }
        }
        public Form1()
        {
            InitializeComponent();
            chart1.Series[0].Points.AddXY("A", 1);
            chart1.Series[0].Points.AddXY("B", 12);
            chart1.Series[0].Points.AddXY("C", 23);
            chart1.Series[0].Points.AddXY("D", 32);
            chart1.Series[0].Points.AddXY("E", 39);
            chart1.Series[0].Points.AddXY("F", 43);
            chart1.Series[0].Points.AddXY("G", 55);
            chart1.Series[0].Points.AddXY("H", 59);
            chart1.Series[0].Points.AddXY("I", 67);
        }
        Point? prevPosition = null;
        ToolTip tooltip = new ToolTip();
        void chart1_MouseMove(object sender, MouseEventArgs e)
        {
            var pos = e.Location;
            if (prevPosition.HasValue && pos == prevPosition.Value)
                return;
            tooltip.RemoveAll();
            prevPosition = pos;
            var results = chart1.HitTest(pos.X, pos.Y, false,
                                       ChartElementType.DataPoint);
            foreach (var result in results)
            {
                if (result.ChartElementType == ChartElementType.DataPoint)
                {
                    var prop = result.Object as DataPoint;
                    if (prop != null)
                    {
                        var pointXPixel = result.ChartArea.AxisX.ValueToPixelPosition(prop.XValue);
                        var pointYPixel = result.ChartArea.AxisY.ValueToPixelPosition(prop.YValues[0]);
                        // check if the cursor is really close to the point (2 pixels around the point)
                        if (Math.Abs(pos.X - pointXPixel) < 2 &&
                            Math.Abs(pos.Y - pointYPixel) < 2)
                        {
                            tooltip.Show("X=" + prop.XValue + ", Y=" + prop.YValues[0], this.chart1,
                                            pos.X, pos.Y - 15);
                        }
                    }
                }
            }

        }

    }
}

将鼠标悬停在折线图上时显示工具提示

试试这个。

这是我的财务（棒，蜡烛）图表的工作。与大多数示例一样，不显示DataPoint的YValue[0]，而是显示Y轴的YValue。

    Point? prevPosition = null;
    ToolTip tooltip = new ToolTip();
    private void chart_MouseMove(object sender, MouseEventArgs e)
    {
        var pos = e.Location;
        if (prevPosition.HasValue && pos == prevPosition.Value)
            return;
        tooltip.RemoveAll();
        prevPosition = pos;
        var results = chart.HitTest(pos.X, pos.Y, false, ChartElementType.DataPoint); // set ChartElementType.PlottingArea for full area, not only DataPoints
        foreach (var result in results)
        {
            if (result.ChartElementType == ChartElementType.DataPoint) // set ChartElementType.PlottingArea for full area, not only DataPoints
            {
                var yVal = result.ChartArea.AxisY.PixelPositionToValue(pos.Y);
                tooltip.Show(((int)yVal).ToString(), chart, pos.X, pos.Y - 15);
            }
        }
    }
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