Execute Powershell Script text in c#, passing values to arguments in Param Section

Question

I have a simple powershell script

param
(

   [Parameter(Mandatory=$true)]
   [int]$loop = 2
)

for ($i=0; $i -le $loop; $i++)
{
  $v += get-process
}

$v

I want to execute it through C#. I am able to execute simple scripts but now when I want to pass value to the $loop parameter it says

{"Cannot process command because of one or more missing mandatory parameters: loop."}

I am using the below code:

using (PowerShell powerShellInstance = PowerShell.Create(RunspaceMode.NewRunspace))
{
    powerShellInstance.Runspace = runspace;
    powerShellInstance.AddScript(script);

    if (parameters != null && parameters.Any())
    {
        foreach (var parameter in parameters)
        {
            if (parameter.Type == ParameterType.Int32)
            {
                int value = Convert.ToInt32(parameter.Value.Trim());
                powerShellInstance.AddParameter(parameter.Name.Trim(), value);
                }
            else
            {
                powerShellInstance.AddParameter(parameter.Name.Trim(), parameter.Value.Trim());
            }
        }
    }

Here, I see in the debug mode of visual studio that the parameter name is $loop and its value is being clearly set through the Addparameter Api

But I get the above exception when I call

Collection<PSObject> output = powerShellInstance.Invoke();

NOt sure, where am I going wrong. Please help

Answer 1

It would help to see the rest of your code where you define parameters and script. One thing to note is that the name of parameter is actually loop, not $loop.

Here is some very simplified code that shows this working.

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Management.Automation;
using System.Text;
using System.Threading.Tasks;

namespace PSTest
{
    class Program
    {
        static void Main(string[] args)
        {
            using (PowerShell powerShellInstance = PowerShell.Create(RunspaceMode.NewRunspace))
            {

                var script = "param($param1) $output = 'testing params in C#:' + $param1; $output";
                powerShellInstance.AddScript(script);
                powerShellInstance.AddParameter("param1", "ParamsinC#");
                Collection<PSObject> PSOutput = powerShellInstance.Invoke();

                foreach (PSObject outputItem in PSOutput)
                {

                    if (outputItem != null)
                    {
                        Console.WriteLine(outputItem);
                    }
                }
                Console.ReadKey();

            }
        }
    }
}