Provides access to events that occur when working with a topology.
Product Availability
Available with ArcGIS Desktop.
Members
| Description | ||
|---|---|---|
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OnActiveErrorsChanged | Called when the active error selection is changed. | 
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OnCurrentTopologyChanged | Called when the current topology is changed. | 
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OnErrorDeleted | Called when a topology error is deleted. | 
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OnTopologySelectionChanged | Called when the topology element selection is changed. | 
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OnValidate | Called when a topology is validated. | 
CoClasses that implement ITopologyExtensionEvents
| CoClasses and Classes | Description | 
|---|---|
| ErrorWindow | Esri topology error inspector. | 
| TopologyExtension | Extension for working with topology. | 
Remarks
TopologyExtension listeners are objects like a command that listen for and respond to events triggered by the topology extension. For example, the OnValidate event is fired each time a topology is validated and a custom object could perform additional tasks after receiving this notification.
[C#]
The following code shows how to wire topology events in C#.
public void WireTopologyEvents()
{
  UID extUid = new UIDClass();
  extUid.Value = "esriEditorExt.TopologyExtension";
  //You can get app from ICommand :: OnCreate() hook parameter
  ITopologyExtension topologyExt = app.FindExtensionByCLSID(extUid) as ITopologyExtension;
  ((ITopologyExtensionEvents_Event)topologyExt).OnTopologySelectionChanged += 
    new ITopologyExtensionEvents_OnTopologySelectionChangedEventHandler(OnTopologySelectionChanged);
}
void OnTopologySelectionChanged()
{
  System.Windows.Forms.MessageBox.Show("Topology selection changed.");
}
 
[Visual Basic .NET]
The following code shows how to wire topology events in VBNet.
  Public Sub WireTopologyEvents()
    'You can get app from ICommand :: OnCreate() hook parameter
    Dim extUid As UID = New UIDClass()
    extUid.Value = "esriEditorExt.TopologyExtension"
    Dim topologyExt As ITopologyExtension = TryCast(app.FindExtensionByCLSID(extUid), ITopologyExtension)
    'Wire editor events.
    AddHandler (CType(topologyExt, ITopologyExtensionEvents_Event).OnTopologySelectionChanged  , AddressOf OnTopologySelectionChanged
  End Sub
  Private Sub OnTopologySelectionChanged()
    System.Windows.Forms.MessageBox.Show("Topology selection changed.")
  End Sub
