DevExpress ChartControl ToolTipPointPattern和ToolTipSeriesPattern

原本只是想改一下鼠標放到曲線上的tip顯示的小數點位數
然後就發現他這個屬性還挺多，多到有點看不懂
然後就寫了小demo測試

demo代碼

// Create a series and add points to it. 
            Series series1 = new Series("Series 1", ViewType.Line);
            series1.Points.Add(new SeriesPoint("A", new double[] { 4.1111 }));
            series1.Points.Add(new SeriesPoint("B", new double[] { 2.2222 }));
            series1.Points.Add(new SeriesPoint("C", new double[] { 17.7777 }));
            series1.Points.Add(new SeriesPoint("D", new double[] { 4.4444 }));
            series1.Points.Add(new SeriesPoint("E", new double[] { 17.7777 }));
            series1.Points.Add(new SeriesPoint("F", new double[] { 12.2222 }));
            series1.Points.Add(new SeriesPoint("G", new double[] { 15.5555 }));

            // Add the series to the chart. 
            chartControl.Series.Add(series1);

            //// Disable a crosshair cursor. 
            chartControl.CrosshairEnabled = DefaultBoolean.True;

            //// Enable chart tooltips.  
            chartControl.ToolTipEnabled = DefaultBoolean.True; 

            //// Specify the tooltip point pattern. 
            series1.ToolTipPointPattern = "ToolTipPoint: {A}:{V:F2}";
            series1.ToolTipSeriesPattern = "ToolTipSeries: {A}:{V:F2}";
            series1.CrosshairLabelPattern = "CrosshairLabel: {A}:{V:F2}";

demo效果

demo結論

結論就很明顯了，ToolTipPoint是鼠標放到點上纔會顯示出來的tip，CrosshairLabel是鼠標放到圖上，它會十字線找到點，再顯示出來。而最後ToolTipSeriesPattern是幹嘛用的，怎樣顯示出來，我也還沒摸清。

Pattern

附上官方的文檔和例程

https://documentation.devexpress.com/WindowsForms/18052/Controls-and-Libraries/Chart-Control/Examples/End-User-Interaction/How-to-Use-Chart-Tooltips

using DevExpress.XtraCharts;
using System;
using System.Windows.Forms;
using DevExpress.Utils;

namespace TooltipCustomization {
    public partial class Form1 : Form {
        public Form1() {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e) {
            // Create an empty chart. 
            ChartControl chartControl = new ChartControl();

            // Add the chart to the form. 
            chartControl.Dock = DockStyle.Fill;
            this.Controls.Add(chartControl);

            // Create a series and add points to it. 
            Series series1 = new Series("Series 1", ViewType.Bar);
            series1.Points.Add(new SeriesPoint("A", new double[] { 4 }));
            series1.Points.Add(new SeriesPoint("B", new double[] { 2 }));
            series1.Points.Add(new SeriesPoint("C", new double[] { 17 }));
            series1.Points.Add(new SeriesPoint("D", new double[] { 4 }));
            series1.Points.Add(new SeriesPoint("E", new double[] { 17 }));
            series1.Points.Add(new SeriesPoint("F", new double[] { 12 }));
            series1.Points.Add(new SeriesPoint("G", new double[] { 15 }));

            // Add the series to the chart. 
            chartControl.Series.Add(series1);

            // Disable a crosshair cursor. 
            chartControl.CrosshairEnabled = DefaultBoolean.False;

            // Enable chart tooltips.  
            chartControl.ToolTipEnabled = DefaultBoolean.True;

            // Show a tooltip's beak 
            ToolTipController controller = new ToolTipController();
            chartControl.ToolTipController = controller;
            controller.ShowBeak = true;

            // Change the default tooltip mouse position to relative position. 
            ToolTipRelativePosition relativePosition = new ToolTipRelativePosition();
            chartControl.ToolTipOptions.ToolTipPosition = relativePosition;

            // Specify the tooltip relative position offsets.   
            relativePosition.OffsetX = 2;
            relativePosition.OffsetY = 2;

            // Specify the tooltip point pattern. 
            series1.ToolTipPointPattern = "Bar Series: {A}:{V}";
        }
    }
}