Topic: How to cast an object into another...

[EDDemtec]

Hi Guys !

I would like to learn how to cast an object into another object of a different type, if it's possible...

In my case, I want to cast an ObjectId in a AecWall and get length of the current wall...

Code: [Select]

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AEC.Interop.ArchBase

Public Class Class1
    <CommandMethod("Class1")> _
    Public Sub Class1()
        '' Get the current document and database, and start a transaction
        Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument
        Dim acCurDb As Database = acDoc.Database

        Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction()
            '' Open the Block table record for read
            Dim acBlkTbl As BlockTable
            acBlkTbl = acTrans.GetObject(acCurDb.BlockTableId, OpenMode.ForRead)

            '' Open the Block table record Model space for read
            Dim acBlkTblRec As BlockTableRecord
            acBlkTblRec = acTrans.GetObject(acBlkTbl(BlockTableRecord.ModelSpace), OpenMode.ForRead)

            Dim myWall As New AecWall

            '' Step through each object in Model space and
            '' display the type of object found
            For Each acObjId As ObjectId In acBlkTblRec
                If acObjId.ObjectClass().DxfName = "AEC_WALL" Then
                    'Get wall length here

                End If
            Next

            '' Dispose of the transaction
        End Using
    End Sub
End Class
Thanks in advance !

[huiz]

DirectCast for example.

[huiz]

Dim ent As Entity = DirectCast(tr.GetObject(myObjectID, OpenMode.ForRead), Entity)

Otherwise you can have a look at TryCast.

[huiz]

Btw, if you only look for one type of object, you can create a Selection with a certain object type as filter. It reduces the loop.

[EDDemtec]

Btw, if you only look for one type of object, you can create a Selection with a certain object type as filter. It reduces the loop.

Thank you for all !

I found the code below, but I dont want to prompt for a selection, is it possible ?

Code: [Select]

Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.EditorInput
Public Class Class2
    <CommandMethod("FilterSelectionSet")> _
    Public Sub FilterSelectionSet()

      '' Get the current document editor
      Dim acDocEd As Editor = Application.DocumentManager.MdiActiveDocument.Editor

      '' Create a TypedValue array to define the filter criteria
      Dim acTypValAr(0) As TypedValue
      acTypValAr.SetValue(New TypedValue(DxfCode.Start, "AEC_WALL"), 0)

      '' Assign the filter criteria to a SelectionFilter object
      Dim acSelFtr As SelectionFilter = New SelectionFilter(acTypValAr)

      '' Request for objects to be selected in the drawing area
      Dim acSSPrompt As PromptSelectionResult
      acSSPrompt = acDocEd.GetSelection(acSelFtr)

      '' If the prompt status is OK, objects were selected
      If acSSPrompt.Status = PromptStatus.OK Then
          Dim acSSet As SelectionSet = acSSPrompt.Value
          Application.ShowAlertDialog("Number of objects selected: " & acSSet.Count.ToString())
      Else
          Application.ShowAlertDialog("Number of objects selected: 0")
      End If

    End Sub
End Class

[Jeff_M]

Look at using the acDocEd.SelectAll(acSelFtr) method instead of the GetSelection() method.

[EDDemtec]

Look at using the acDocEd.SelectAll(acSelFtr) method instead of the GetSelection() method.

Thank you very much for your help !

As sample, the code below, select all walls in the drawing...

Code: [Select]

Public Class FilterSelectionAll

    'Define the command
    <CommandMethod("fsa")> _
    Public Sub fsa()

        '' Get the current document editor
        Dim acDocEd As Editor = Application.DocumentManager.MdiActiveDocument.Editor

        '' Create a TypedValue array to define the filter criteria
        Dim acTypValAr(0) As TypedValue
        acTypValAr.SetValue(New TypedValue(DxfCode.Start, "AEC_WALL"), 0)

        '' Assign the filter criteria to a SelectionFilter object
        Dim acSelFtr As SelectionFilter = New SelectionFilter(acTypValAr)

        '' Request for objects to be selected in the drawing area
        Dim acSSPrompt As PromptSelectionResult
        acSSPrompt = acDocEd.SelectAll(acSelFtr)

        '' If the prompt status is OK, objects were selected
        If acSSPrompt.Status = PromptStatus.OK Then
            Dim acSSet As SelectionSet = acSSPrompt.Value
            Application.ShowAlertDialog("Number of objects selected: " & acSSet.Count.ToString())
        Else
            Application.ShowAlertDialog("Number of objects selected: 0")
        End If

    End Sub

End Class