You can merge multiple selection sets be creating an ObjectIdCollection object and then adding the object ids from multiple selection sets together. In addition to adding object ids to an ObjectIdCollection object, you can remove object ids. Once all object ids are added to an ObjectIdCollection object, you can iterate through the collection of object ids and manipulate each object as needed.
Add selected objects to a selection set
This example prompts the user to select objects twice and then merges the two selection sets created into a single selection set.
Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.EditorInput
<CommandMethod("MergeSelectionSets")> _Public Sub MergeSelectionSets()
'' Get the current document editor
Dim acDocEd As Editor = Application.DocumentManager.MdiActiveDocument.Editor
'' Request for objects to be selected in the drawing area
Dim acSSPrompt As PromptSelectionResult
acSSPrompt = acDocEd.GetSelection()
Dim acSSet1 As SelectionSet
Dim acObjIdColl As ObjectIdCollection = New ObjectIdCollection()
'' If the prompt status is OK, objects were selected
If acSSPrompt.Status = PromptStatus.OK Then
'' Get the selected objects
acSSet1 = acSSPrompt.Value
'' Append the selected objects to the ObjectIdCollection
acObjIdColl = New ObjectIdCollection(acSSet1.GetObjectIds())
End If
'' Request for objects to be selected in the drawing area
acSSPrompt = acDocEd.GetSelection()
Dim acSSet2 As SelectionSet
'' If the prompt status is OK, objects were selected
If acSSPrompt.Status = PromptStatus.OK Then
acSSet2 = acSSPrompt.Value
'' Check the size of the ObjectIdCollection, if zero, then initialize it
If acObjIdColl.Count = 0 Then
acObjIdColl = New ObjectIdCollection(acSSet2.GetObjectIds())
Else
Dim acObjId As ObjectId
'' Step through the second selection set
For Each acObjId In acSSet2.GetObjectIds()
'' Add each object id to the ObjectIdCollection
acObjIdColl.Add(acObjId)
Next
End If
End If
Application.ShowAlertDialog("Number of objects selected: " & _acObjIdColl.Count.ToString())
End Sub
using Autodesk.AutoCAD.Runtime;
using Autodesk.AutoCAD.ApplicationServices;
using Autodesk.AutoCAD.DatabaseServices;
using Autodesk.AutoCAD.EditorInput;
[CommandMethod("MergeSelectionSets")]public static void MergeSelectionSets()
{// Get the current document editor
Editor acDocEd = Application.DocumentManager.MdiActiveDocument.Editor;
// Request for objects to be selected in the drawing area
PromptSelectionResult acSSPrompt;
acSSPrompt = acDocEd.GetSelection();
SelectionSet acSSet1;
ObjectIdCollection acObjIdColl = new ObjectIdCollection();
// If the prompt status is OK, objects were selected
if (acSSPrompt.Status == PromptStatus.OK)
{// Get the selected objects
acSSet1 = acSSPrompt.Value;
// Append the selected objects to the ObjectIdCollection
acObjIdColl = new ObjectIdCollection(acSSet1.GetObjectIds());
}
// Request for objects to be selected in the drawing area
acSSPrompt = acDocEd.GetSelection();
SelectionSet acSSet2;
// If the prompt status is OK, objects were selected
if (acSSPrompt.Status == PromptStatus.OK)
{acSSet2 = acSSPrompt.Value;
// Check the size of the ObjectIdCollection, if zero, then initialize it
if (acObjIdColl.Count == 0)
{acObjIdColl = new ObjectIdCollection(acSSet2.GetObjectIds());
}
else
{// Step through the second selection set
foreach (ObjectId acObjId in acSSet2.GetObjectIds())
{// Add each object id to the ObjectIdCollection
acObjIdColl.Add(acObjId);
}
}
}
Application.ShowAlertDialog("Number of objects selected: " +acObjIdColl.Count.ToString());
}
