How can I preview the PowerShell command before execute?

Question

Let's say I have the following PowerShell source:

PowerShell shell = PowerShell.Create().AddCommand("Get-NetAdapter")
                                      .AddParameter("name", "Ethernet*")
                                      .AddParameter("ThrottleLimit", 5);

Now, before call shell.Invoke(), I want check, for logging purposes, the final command line. In this case I expect something like

Get-NetAdapter -name Ethernet* -ThrottleLimit 5

I tested these, but none works:

shell.Commands.ToString()
shell.Commands.Commands.ToString()
shell.Commands.Commands.First().CommandText
shell.Commands.Commands.First().ToString()

Is there some built in way to check the final command line?

Answer 1

How about:

namespace SomeProject.Extensions
{
    using System;
    using System.Management.Automation;
    using System.Management.Automation.Runspaces;
    using System.Text;

    public static class PowerShellExtensions
    {
        public static void LogCommandLine(this PowerShell commandToLog)
        {
            foreach (Command command in commandToLog.Commands.Commands)
            {
                StringBuilder commandLine = new StringBuilder(command.ToString());

                foreach (CommandParameter parameter in command.Parameters)
                {
                    commandLine.Append($" --{parameter.Name} {parameter.Value}");
                }

                Console.WriteLine(commandLine.ToString());
            }
        }
    }
}

which given

namespace SomeProject.Extensions.UnitTests
{
    using System.Management.Automation;
    using NUnit.Framework;

    [TestFixture]
    [Parallelizable(ParallelScope.All)]
    [System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
    public class PowerShellExtensionsTests
    {
        [Test]
        [Category(nameof(PowerShellExtensions))]
        public void TestCommandLine()
        {
            PowerShell shell = PowerShell.Create().AddCommand("Get-NetAdapter")
                                                  .AddParameter("name", "Ethernet*")
                                                  .AddParameter("ThrottleLimit", 5);

            shell.LogCommandLine();
        }
    }
}

Outputs what you wanted:

Get-NetAdapter --name Ethernet* --ThrottleLimit 5

Given more complex parameters, you may need to get more fancy as it will just output the type of the parameter and not necessarily a nice string representation of it.