I'm using PowerShell script to run C# code directly in the script. I've run in to an error a particular error a few times. If I make any changes to the C# code in the PowerShell ISE and try to run it again I get the following error.
Add-Type : Cannot add type. The type name 'AlertsOnOff10.onOff' already exists.
At C:\Users\testUser\Desktop\test.ps1:80 char:1
+ Add-Type -TypeDefinition $Source -ReferencedAssemblies $Assem
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation: (AlertsOnOff10.onOff:String) [Add-Type], Exception
+ FullyQualifiedErrorId : TYPE_ALREADY_EXISTS,Microsoft.PowerShell.Commands.AddTypeCommand
The way I have been resolving this error is by changing the namespace and the command to call the C# method [AlertsOnOff10.onOff]::Main("off"). I there a way I can prevent this error from happening without having to change namespace and method call?
To my knowledge there is no way to remove a type from a PowerShell session once it has been added.
The (annoying) workaround I would suggest is to write your code in one ISE session, and execute it in a completely different session (separate console window or separate ISE if you want to be able to debug).
This only matters if you're changing $Source though (actively developing the type definition). If that's not the part that's changing, then ignore the errors, or if it's a terminating error use -ErrorAction to change it.