How to resolve assemblies in ACAD 2015 SP2 [Serializat​ionExcepti​on Only Affecting AutoCAD 2015 SP2]

By Madhukar Moogala

With ACAD 2015 SP2 , application no longer resolves assemblies that is if an application is using any dependent DLL and are not located in host application directory ,the plugin application may crash as it is failed to load those dlls

I came to know from my engineering colleague Art, recently he has responded a query on similar issue on forum Serialization Exception

This blog intention is to target larger audience.

Imports System
Imports Autodesk.AutoCAD.Runtime
Imports Autodesk.AutoCAD.ApplicationServices
Imports Autodesk.AutoCAD.DatabaseServices
Imports Autodesk.AutoCAD.Geometry
Imports Autodesk.AutoCAD.EditorInput
'dependent assembly
Imports ThreadSafe
Imports System.Reflection
 
' This line is not mandatory, but improves loading performances

Namespace TestVB15
 
Public Class MyCommands   _
        Public Sub MyCommand()
 
AddHandler AppDomain.CurrentDomain.AssemblyResolve, _
AddressOf OnAssemblyResolve
  'TestObject is class from custom made ThreadSafe dll namespace
Dim TstObj As New TestObject
Dim TstObjBts As Byte() = TstObj.ToBytes
Dim TstObj2 As TestObject = _
ThreadSafeDataClass.FromBytes(Of TestObject)(TstObjBts)
Dim TstObjs As New TestObjects
TstObjs.Add(TstObj)
TstObjs.Add(TstObj2)
Dim TstObjsBts As Byte() = TstObjs.ToBytes
Dim TstObjs2 As TestObjects =
ThreadSafeDataClass.FromBytes(Of TestObjects)(TstObjsBts)
TstObjs2.Add(New TestObject)
End Sub
 
 
 
 Private Shared Function OnAssemblyResolve(
sender As Object, args As ResolveEventArgs) As Assembly
 Dim assembly As Assembly = Nothing
 Dim assems As [Assembly]() =_ AppDomain.CurrentDomain.GetAssemblies()
Dim shortName As String = _
args.Name.Split(New [Char]() {","}).GetValue(0)
'ThreasSafe dependent Assembly 
Dim threadSafe As String = "ThreadSafe"
 
 'check that the assembly being asked for is one of ours and if it is not, then return nothing
If shortName  threadSafe Then
 Return assembly
End If
 
For Each assem In assems
If assem.GetName.Name = shortName Then
Return assem
End If
Next assem
 'if assembly is not loaded ,we 'll explictly load this maymay not be required
Dim an = New AssemblyName(args.Name)
If an.Name  args.Name Then
assembly = DirectCast(sender, AppDomain).Load(an.Name)
End If
Return assembly
End Function
End Class
End Namespace