优劣势

ZedGraph 相较同类工具的优势：

• 功能完备，bug 少
• 用户基数大，Bing 搜问题方便

劣势：

• 从 2012 后基本停止维护
• 官网没了，对新上手的小伙伴不友好
  • 该问题可以通过浏览 ZedDemo.7z 中的示例项目得到解决

PS：虽然已停止维护快 10 年了，但还能被评为 14 个最好的 .NET 免费控件，希望能有更好的绘图库来替代 ZedGraph 的使命吧。

简介

ZedGraph 是一个强大的 .NET 图形绘制库。

The charting library for .NET

相关资源：

• GitHub
• NuGet
• Wiki
• 作者写的介绍
• ZedGraph Help.zip
• ZedDemo.7z

支持平台：

• .NET Framework

  基本使用

  从 作者写的介绍 中摘抄得来。

第一步：从控件库中拖一个 ZedGraphControl 到 Form 上。

第二步：通过代码初始化并绘制图形。

private void Form1_Load( object sender, EventArgs e )
{
   // Setup the graph
   CreateGraph( zedGraphControl1 );
}
// Build the Chart
private void CreateGraph( ZedGraphControl zgc )
{
   // get a reference to the GraphPane
   GraphPane myPane = zgc.GraphPane;
   // Set the Titles
   myPane.Title.Text = "My Test Graph\n(For CodeProject Sample)";
   myPane.XAxis.Title.Text = "My X Axis";
   myPane.YAxis.Title.Text = "My Y Axis";
   // Make up some data arrays based on the Sine function
   double x, y1, y2;
   PointPairList list1 = new PointPairList();
   PointPairList list2 = new PointPairList();
   for ( int i = 0; i < 36; i++ )
   {
      x = (double)i + 5;
      y1 = 1.5 + Math.Sin( (double)i * 0.2 );
      y2 = 3.0 * ( 1.5 + Math.Sin( (double)i * 0.2 ) );
      list1.Add( x, y1 );
      list2.Add( x, y2 );
   }
   // Generate a red curve with diamond
   // symbols, and "Porsche" in the legend
   LineItem myCurve = myPane.AddCurve( "Porsche",
         list1, Color.Red, SymbolType.Diamond );
   // Generate a blue curve with circle
   // symbols, and "Piper" in the legend
   LineItem myCurve2 = myPane.AddCurve( "Piper",
         list2, Color.Blue, SymbolType.Circle );
   // Tell ZedGraph to refigure the
   // axes since the data have changed
   zgc.AxisChange();
}

效果：

使用技巧

给柱状图加数值标识

方法一，使用自带的 CreateBarLabels：

BarItem.CreateBarLabels(myPane, false, "f0", "Arial", 28, Color.CadetBlue, false, false, false);

注：如果要清理这些 label，需要使用 zgc.GraphPane.GraphObjList.Clear();。

方法二，手动绘制：

var myPane = zgc.GraphPane;
var fontSpec = myPane.Legend.FontSpec.Clone();
fontSpec.Family = "Microsoft YaHei";
fontSpec.Size = 22;
fontSpec.Border.IsVisible = false;
fontSpec.Fill.IsVisible = false;
var text = new TextObj("2.33", 0.55, 2.33)
{
    Location = { CoordinateFrame = CoordType.AxisXYScale, AlignH = AlignH.Left, AlignV = AlignV.Center },
    FontSpec = fontSpec
};
myPane.GraphObjList.Add(text);

修改右键菜单

参考 Edit the Context Menu

移除或禁用现有菜单项：

private void MyContextMenuBuilder(
    ZedGraphControl control, ContextMenuStrip menuStrip, 
    Point mousePt,ZedGraphControl.ContextMenuObjectState objState)
{
   foreach( ToolStripMenuItem item in menuStrip.Items )
   {
      if ( (string) item.Tag == "set_default" )
      {
         // remove the menu item
         menuStrip.Items.Remove( item );
         // or, just disable the item with this
         //item.Enabled = false; 
         break;
      }
   }
}

添加新的右键菜单项：

private void MyContextMenuBuilder( 
    ZedGraphControl control, ContextMenuStrip menuStrip, 
    Point mousePt,ZedGraphControl.ContextMenuObjectState objState )
{   
   // create a new menu item
   ToolStripMenuItem item = new ToolStripMenuItem();
   // This is the user-defined Tag so you can find this menu item later if necessary
   item.Name = "my_special_tag";
   item.Tag = "my_special_tag";
   // This is the text that will show up in the menu
   item.Text = "Do Something Special";
   // Add a handler that will respond when that menu item is selected
   item.Click += new System.EventHandler( DoSomethingSpecial );
   // Add the menu item to the menu
   menuStrip.Items.Add( item );
}
protected void DoSomethingSpecial( object sender, System.EventArgs e )
{
   // do something here.  For example, remove all curves from the graph
   zedGraphControl1.GraphPane.CurveList.Clear();
   zedGraphControl1.Refresh();
}

示例 - 右键菜单中增加导出为 CSV 功能

参考：ZedGraph C# Graph Data Export to CSV Using a Custom Context Menu

private void InitializeZedGraph(ZedGraphControl zgc)
{
    ...
    zgc.ContextMenuBuilder += Zgc_ContextMenuBuilder;
}
private void Zgc_ContextMenuBuilder(ZedGraphControl sender, ContextMenuStrip menuStrip, Point mousePt, ZedGraphControl.ContextMenuObjectState objState)
{
    var item = new ToolStripMenuItem
    {
        Name = "Export Data as CSV",
        Tag = "export_data_csv",
        Text = "导出波形数据为 CSV"
    };
    item.Click += ShowSaveAsForExportCSV;
    menuStrip.Items.Insert(2, item);
}
private StreamWriter _csvWriter;
private void ShowSaveAsForExportCSV(object sender, EventArgs e)
{
    try
    {
        var dialogExportCSV = new SaveFileDialog
        {
            Filter = @"CSV Files|*.csv",
            Title = @"Export Profile",
            FileName = ZgcMain.GraphPane.Title.Text
        };
        if (dialogExportCSV.ShowDialog() != DialogResult.OK) return;
        _csvWriter = new StreamWriter(dialogExportCSV.FileName);
        WriteCSVToStream();
        _csvWriter.Close();
        MessageBox.Show("CSV 波形文件已保存", "波形导出", MessageBoxButtons.OK);
    }
    catch (Exception ex)
    {
        _csvWriter.Close();
        MessageBox.Show(ex.ToString());
    }
}
private void WriteCSVToStream()
{
    var xAxisHeader = ZgcMain.GraphPane.XAxis.Title.Text;
    var yAxisHeader = ZgcMain.GraphPane.YAxis.Title.Text;
    _csvWriter.Write(xAxisHeader + "," + yAxisHeader + "\n");
    for (var i = 0; i < _currentPointList.Count; i++)
    {
        _csvWriter.Write(_currentPointList[i].X + "," + _currentPointList[i].Y + "\n");
    }
}

获取当前点击的 Pane

当一个 Zed 上面有多个 Pane 时，可以用FinNearestPaneObject方法获取点击的 Pane。

当然该方法也可以用作获取其它 Object。

using (var g = zed.CreateGraphics())
{
    int iPt;
    GraphPane pane; object nearestObj;
    zed.MasterPane.FindNearestPaneObject(e.Location, g, out pane,out nearestObj,out iPt);
    pane.Border=new Border(Color.FromArgb(0,122,204),2);
}

在一行并排显式两个 Pane

首先你要有两个 Pane，再通过SetLayout设置显式模式为SingleRow即可。

切换显式模式还可以得到 211、112、Square 等效果。

var zed = ZedGraphMain;
var master = zed.MasterPane;
var leftPane = master.PaneList[0];
var rightPane = leftPane.Clone();
rightPane.CurveList.Clear();
master.Add(rightPane);
// Tell ZedGraph to auto layout all the panes
using (var g = zed.CreateGraphics())
{
    master.SetLayout(g, PaneLayout.SingleRow);
    master.AxisChange(g);
}
zed.AxisChange();
zed.Refresh();