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Selection Event

When WantSelectionEvent property of KernelCAD Context is true (false is the default) the application receives KernelCAD Event notification when the user makes multile selection in Direct User Access mode

Tthe eventType parameter of the selection event is the EDIEvent.eEventSelection member of EDIEvent enumeration

The param0 parameter of the event is an integer which indicates what kind of items is selected. Possible values are enumerated in EElemTypeKC enumeration. In v4.1 it can be EElemTypeKC.eElTypeVertex or EElemTypeKC.eElTypeSection only. Contact us to request notification about the other types

As there are several sources of the KernelCAD Event the event handler has to check for the correct type of event and allow the handler to exit without any action if the event is different from one described above.

When selection is cleared by the end user the component raises similar KernelCAD Event passing an empty list. The eventType parameter in the case is EDIEvent.eEventSelection and param0 is an integer with value EElemTypeKC.eElTypeUnknown.

Multiple Vertex Selection

The param1 parameter of the event is an IList interface passed out as IUnkknown type. Elements of the list have IVertex type, which gives acess to coordinates and normals of the vertex.

Query ISection, IMesh, IMeshEx, etc from the IList to get access to properties of the object and/or mesh, which own the vertex.

See MeshMods sample for an example.

Multiple Object Selection

The param1 parameter of the event is an IList interface passed out as IUnkknown type. Elements of the list have ISection type, which gives acess to all properties of the object.

In .NET language use convertion similar to:

IntPtr pSection = iList.GetAt(pos);

ISection iSect = (ISection)Marshal.GetObjectForIUnknown(pSection);

To convert items of the list to ISection type

See Pick sample for an example.