GetObjectIds to ObjectIdCollection

ObjectId() to ObjectIdCollection

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

‘用Copyto 可将ObjectIdCollection转为ObjectId()
Dim NewIDS As New ObjectIdCollection
Dim NewIDArray As ObjectId() = New ObjectId(NewIDS.Count - 1) {} '必须提前初始化，不能用nothing
NewIDS.CopyTo(NewIDArray, 0)