How to properly add .NET assemblies to Powershell session?
- by amandion
I have a .NET assembly (a dll) which is an API to backup software we use here. It contains some properties and methods I would like to take advantage of in my Powershell script(s). However, I am running into a lot of issues with first loading the assembly, then using any of the types once the assembly is loaded.
The complete file path is:
C:\rnd\CloudBerry.Backup.API.dll
In Powershell I use:
$dllpath = "C:\rnd\CloudBerry.Backup.API.dll"
Add-Type -Path $dllpath
I get the error below:
Add-Type : Unable to load one or more of the requested types. Retrieve the
LoaderExceptions property for more information.
At line:1 char:9
+ Add-Type <<<< -Path $dllpath
+ CategoryInfo : NotSpecified: (:) [Add-Type], ReflectionTypeLoadException
+ FullyQualifiedErrorId : System.Reflection.ReflectionTypeLoadException,Microsoft.PowerShell.Commands.AddTypeComma
ndAdd-Type : Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
Using the same cmdlet on another .NET assembly, DotNetZip, which has examples of using the same functionality on the site also does not work for me.
I eventually find that I am seemingly able to load the assembly using reflection:
[System.Reflection.Assembly]::LoadFrom($dllpath)
Although I don't understand the difference between the methods Load, LoadFrom, or LoadFile that last method seems to work.
However, I still seem to be unable to create instances or use objects. Each time I try, I get errors that describe that Powershell is unable to find any of the public types.
I know the classes are there:
$asm = [System.Reflection.Assembly]::LoadFrom($dllpath)
$cbbtypes = $asm.GetExportedTypes()
$cbbtypes | Get-Member -Static
---- start of excerpt ----
TypeName: CloudBerryLab.Backup.API.BackupProvider
Name MemberType Definition
---- ---------- ----------
PlanChanged Event System.EventHandler`1[CloudBerryLab.Backup.API.Utils.ChangedEventArgs] PlanChanged(Sy...
PlanRemoved Event System.EventHandler`1[CloudBerryLab.Backup.API.Utils.PlanRemoveEventArgs] PlanRemoved...
CalculateFolderSize Method static long CalculateFolderSize()
Equals Method static bool Equals(System.Object objA, System.Object objB)
GetAccounts Method static CloudBerryLab.Backup.API.Account[], CloudBerry.Backup.API, Version=1.0.0.1, Cu...
GetBackupPlans Method static CloudBerryLab.Backup.API.BackupPlan[], CloudBerry.Backup.API, Version=1.0.0.1,...
ReferenceEquals Method static bool ReferenceEquals(System.Object objA, System.Object objB)
SetProfilePath Method static System.Void SetProfilePath(string profilePath)
----end of excerpt----
Trying to use static methods fail, I don't know why!!!
[CloudBerryLab.Backup.API.BackupProvider]::GetAccounts()
Unable to find type [CloudBerryLab.Backup.API.BackupProvider]: make sure that the assembly containing this type is load
ed.
At line:1 char:42
+ [CloudBerryLab.Backup.API.BackupProvider] <<<< ::GetAccounts()
+ CategoryInfo : InvalidOperation: (CloudBerryLab.Backup.API.BackupProvider:String) [], RuntimeException
+ FullyQualifiedErrorId : TypeNotFound
Any guidance appreciated!!
