Imports Autodesk.AutoCAD.Runtime Imports Autodesk.AutoCAD.ApplicationServices Imports Autodesk.AutoCAD.DatabaseServices Imports Autodesk.AutoCAD.Geometry Imports Autodesk.AutoCAD.EditorInput Imports Autodesk.AutoCAD.Interop Imports System.Object Imports Autodesk.AutoCAD.Interop.Common Imports Autodesk.AutoCAD.Internal.Forms Imports System Imports System.IO Imports System.Runtime.InteropServices Namespace TestSelecting Public Class MyCommands <CommandMethod("Program")> Public Sub Program() '' Get the current document editor Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument Dim acCurDb As Database = acDoc.Database Dim acDocEd As Editor = acDoc.Editor Dim AcadApp As Autodesk.AutoCAD.Interop.AcadApplication Dim acadDoc As Autodesk.AutoCAD.Interop.AcadDocument AcadApp = CType(GetObject(, "AutoCAD.Application.18.2"), Autodesk.AutoCAD.Interop.AcadApplication) '' Start a transaction Using acTrans As Transaction = acCurDb.TransactionManager.StartTransaction() Dim ssetObj As AcadSelectionSet '' Request for objects to be selected in the drawing area Dim acSSPrompt As PromptSelectionResult = acDocEd.GetSelection(acSelFtr) '' If the prompt status is OK, objects were selected If acSSPrompt.Status = PromptStatus.OK Then Dim acSSet As SelectionSet = acSSPrompt.Value '' Step through the objects in the selection set For Each acSSObj As SelectedObject In acSSet '' Check to make sure a valid SelectedObject object was returned If Not IsDBNull(acSSObj) Then '' Open the selected object for write Dim acEnt As Entity = CType(acTrans.GetObject(acSSObj.ObjectId, OpenMode.ForWrite), Entity) If Not IsDBNull(acEnt) Then acadDoc = AcadApp.ActiveDocument Dim point(0 To 2) As Double point(0) = 2.0 point(1) = 2.0 point(2) = 0.0 Dim afterWMFObj As Object afterWMFObj = acadDoc.Import("C:\Users\C\Documents\Drawing1.wmf"
, point, 2.0) Dim newEntity As Entity = CType((acTrans.GetObject(CType(afterWMFObj, ObjectId), OpenMode.ForWrite)), Entity) newEntity.ColorIndex = 3 End If End If Next '' Save the new object to the database acTrans.Commit() End If '' Dispose of the transaction End Using End Sub End Class End Namespace
************** Exception Text ************** System.InvalidCastException: Specified cast is not valid. at TestSelectingFiltering.TestSelecting.MyCommands.Fi
lterBlueCircleOnLayer0() at Autodesk.AutoCAD.Runtime.CommandClass.InvokeWorker (MethodInfo mi, Object commandObject, Boolean bLispFunction) at Autodesk.AutoCAD.Runtime.CommandClass.InvokeWorker WithExceptionFilter(MethodInfo mi, Object commandObject, Boolean bLispFunction) at Autodesk.AutoCAD.Runtime.PerDocumentCommandClass.I nvoke(MethodInfo mi, Boolean bLispFunction) at Autodesk.AutoCAD.Runtime.CommandClass.CommandThunk .Invoke()
I'm trying to be able to add the results from the imported WMF into an entity, so that I'll be able to modify it later.
I keep getting this error. In this code I'm trying to change the imported WMF drawing to a green color.
Any help would be Awesome! -Thanks
Solved! Go to Solution.
Have you debugged by stepping through the code line-by-line? Instead of posting a big chunk of code and exception message at the end, it would be nicer to people who may help you to do your due dilligent work to pointing out which line of the code actually causes the exception.
There are a few things regarding your code:
1. It is not necessary to use VB's GetObject() to get an COM AutoCAD application object. It is especially not good to tie the code with specific version of AutoCAD by using "AutoCAD.Application.18.2", becuse your code is .NET API code that runs inside AutoCAD, whatever version it is would be irrelevent. You obtain the COM AcadApplication by:
As matter of fact, you do not need an AcadApplication object in this importing process. What you need is AcadDocument from current MdiActiveDocument:
Dim acadDoc As AcadDocument=CType(Application.DocumentManager.Mdi
2. I do not see why asking user to select entity or entities and has anything to do with importing WMF. Or maybe you just omitted something irrelevant with this exception, if so, forget my questioning on this.
3. From my observation of the code, the exception is after the importing is completed and when you attempt to obtain the imported entity:
Dim newEntity As Entity = CType((acTrans.GetObject(CType(afterWMFObj, ObjectId), OpenMode.ForWrite)), Entity)
Do you know what type of entity is created when an WMF file is imported into AutoCAD? It is definitely not an ObjectId in Autodesk.AutoCAD.DatabaseService namespace, thus CType(afterWMFObj, ObjectId) fails.
According to AutoCAD VBA help document, WMF file is imported into AutoCAD as AcadBlockreference (an COM object). So, after imported into AutoCAD in .NET API code, you need to obtain an .NET API object froom the COM object. The code would be like:
Dim afterWMFObj As Object
afterWMFObj = acadDoc.Import("C:\Users\C\Documents\Drawing1.wmf"
Dim objId As ObjectId = Entity.FromAcadObject(afterWMFObj)
Dim newEnt As Entity=acTrans.GetObject(objId,OpenMode.ForWrite)