How to run PowerShell from C# as administrator?

Question

I want to execute some PowerShell script through C# but it requires admin privilege. This is my code (I got it here):

using (new Impersonator("user", "domain", "password"))
{
    // create Powershell runspace
    Runspace runspace = RunspaceFactory.CreateRunspace();

    // open it
    runspace.Open();

    // create a pipeline and feed it the script text
    Pipeline pipeline = runspace.CreatePipeline();
    pipeline.Commands.AddScript(scriptText);

    // add parameters if any
    foreach (var parameter in parameters)
    {
        pipeline.Commands[0].Parameters.Add(parameter.Key, parameter.Value);
    }

    // add an extra command to transform the script
    // output objects into nicely formatted strings

    // remove this line to get the actual objects
    // that the script returns. For example, the script

    // "Get-Process" returns a collection
    // of System.Diagnostics.Process instances.
    pipeline.Commands.Add("Out-String");

    // execute the script
    Collection<PSObject> results = pipeline.Invoke();

    // close the runspace
    runspace.Close();

    // convert the script result into a single string
    StringBuilder stringBuilder = new StringBuilder();
    foreach (PSObject obj in results)
    {
        stringBuilder.AppendLine(obj.ToString());
    }

    return stringBuilder.ToString();
}

Anyway, this doesn't work on my machine. For example, if the script text is "Set-ExecutionPolicy Unrestricted" then I get "Access to the registry key 'HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\PowerShell\1\ShellIds\Microsoft.PowerShell' is denied."

And in my case, it cannot get list of virtual machines through Get-VM command. (I found that Get-VM only return results if it runs under Admin privilege.)

Do I do something wrong? Is there another solution for this problem?

Solution

This will launch PowerShell as an Administrator:

var newProcessInfo = new System.Diagnostics.ProcessStartInfo();
newProcessInfo.FileName = @"C:\Windows\SysWOW64\WindowsPowerShell\v1.0\powershell.exe";
newProcessInfo.Verb = "runas";
System.Diagnostics.Process.Start(newProcessInfo);

If you need to pass in a script to run, then use:

newProcessInfo.Arguments = @"C:\path\to\script.ps1";