标签: msagl

我正在构建一个简单的示例应用程序来测试 MSAGL，但如果我在显示图形后添加一条边，则会收到 KeyNotFoundException。

我想这与我需要以某种方式刷新一些数据有关 - 或者可能使用另一种方法，但不知道如何。

样本：

private void MainWindow_Loaded(object sender, RoutedEventArgs e) {
    GraphViewer graphViewer = new GraphViewer();
    graphViewer.BindToPanel(Panel);
    Graph graph = new Graph();

    graph.AddEdge("A", "B");

    graphViewer.MouseUp += (s, ev) =>
    {
        if (graphViewer.ObjectUnderMouseCursor != null)
        {
            graph.AddEdge("A", "C"); // BOOM!
        }
    };

    graph.Attr.LayerDirection = LayerDirection.LR;
    graphViewer.Graph = graph;
}

异常详细信息：

System.Collections.Generic.KeyNotFoundException was unhandled
  HResult=-2146232969
  Message=The given key was not present in the dictionary.
  Source=mscorlib
  StackTrace:
       at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
       at Microsoft.Msagl.WpfGraphControl.GraphViewer.<CreateVNode>b__1d(Edge e) in c:\Users\br\Desktop\MSAGL\automatic-graph-layout-master\GraphLayout\tools\WpfGraphControl\GraphViewer.cs:line 1263
       at Microsoft.Msagl.WpfGraphControl.VNode.<get_OutEdges>b__10(Edge e) in …