Topic: Trapping COM error

[57gmc]

Hi guys.

I still haven't gotten my legacy stuff converted yet, so I'm using AcadApplication.LoadDVB. However, if the vba environment didn't get installed or there was a problem loading the dvb, acad spits out "Automation Error: ****" and then my dll stops execution.  I have this in a try block thinking that a runtime exception would get thrown, but it doesn't. Do you know of any way to trap the COM error so I can recover from it?

[BlackBox]

Not sure if this helps:

Code - vb.net: [Select]

1. Imports System
2. Imports System.IO
3. Imports System.Security.Principal
4.  
5. Imports Autodesk.AutoCAD.ApplicationServices
6. Imports Autodesk.AutoCAD.DatabaseServices
7. Imports Autodesk.AutoCAD.EditorInput
8. Imports Autodesk.AutoCAD.Geometry
9. Imports Autodesk.AutoCAD.Runtime
10.  
11. Namespace Foo
12.  
13.     Public Class FooCommands
14.  
15.         <CommandMethod("FINDVBA")> _
16.         Public Sub FINDVBA()
17.             Dim acDoc As Document = Application.DocumentManager.MdiActiveDocument
18.             Dim ed As Editor = acDoc.Editor
19.             Dim oDb As Database = acDoc.Database
20.             Dim filePath As String
21.             Try
22.                 filePath = HostApplicationServices.Current.FindFile("AcVBA.arx", oDb, FindFileHint.Default)
23.                 If filePath <> Nothing Then
24.                     ed.WriteMessage(vbLf & filePath & vbLf)
25.                 Else
26.                     ed.WriteMessage(vbLf & "** AcVBA.arx not found ** " & vbLf)
27.                 End If
28.             Catch ex As Exception
29.                 ed.WriteMessage(vbLf & "** An exception has occurred ** " & vbLf)
30.             End Try
31.         End Sub
32.  
33.     End Class
34.  
35. End Namespace
36.  

[57gmc]

Thanks. Originally, I had System.Exception in my catch statement, but I switched it for Autodesk.AutoCAD.Runtime.Exception. Shoulda kept it the way it was.

[Kerry]

I'm pretty sure that

Code - vb.net: [Select]

1. Catch ex As Exception

will throw an error ... something like Ambigious Reference

[BlackBox]

Maybe it was the project I was in; there was no listed error, but admittedly I did not debug.

When I read Ed's reply, I recall having to change Exception as he stated above to mitigate the ambiguous error in previous projects.

Ironically, I actually posted that code for the FindFile usage, and not the Try Catch structure. LoL.