C# passing an array to a powershell script

Question

I'm attempting to run a powershell script from C#. I have no problem passing strings to the script however when I try to pass an array to the powershell script an exception gets thrown. Here is the C# code:

string [] test = {"1","2","3","4"};

RunspaceConfiguration runspaceConfiguration = RunspaceConfiguration.Create();
Runspace runspace = RunspaceFactory.CreateRunspace(runspaceConfiguration);

runspace.ApartmentState = System.Threading.ApartmentState.STA;
runspace.ThreadOptions = PSThreadOptions.UseCurrentThread;

runspace.Open();
RunspaceInvoke invoker = new RunspaceInvoke();
invoker.Invoke("Set-ExecutionPolicy Unrestricted");

Pipeline pipeline = runspace.CreatePipeline();
Command myCmd = new Command(@"C:\test.ps1");
CommandParameter param = new CommandParameter("responseCollection", test);
myCmd.Parameters.Add(param);
pipeline.Commands.Add(myCmd);

// Execute PowerShell script
Collection<PSObject> results = pipeline.Invoke();

Here is the powershell script:

param([string[]] $reponseCollection)
$a = $responseCollection[0]

Every time this code executes it throws:

Cannot index into a null array.

I know that the code to execute the powershell script is correct when passing strings to the powershell script, it has been thoroughly tested.

Answer 1

It works perfectly fine for me.

Only thing I notice is that, in your script params you have $reponseCollection - the s is missing in response. Unless you made a mistake in entering it here, that would be the reason.

It might have seemed to work with string because Powershell doesn't care ( normally) when you assign / use a non-existing variable. But when you index into a null / non-existing variable, it does throw the error.