Return powershell variable value to c# application - c#

I am running powershell script from c#.
string scriptPath = "/script/myscript.ps1";
Runspace runspace = RunspaceFactory.CreateRunspace();
runspace.Open();
Pipeline pipeline = runspace.CreatePipeline();
pipeline.Commands.AddScript(scriptPath);
Collection<PSObject> results = pipeline.Invoke();
for example if my myscript.ps1 file below;
$test=4
$test++
$test
How to get the variable test value after executing the script. I need to get that value to my c# program.

I know I am late to this, but in your script, you need to add global: in front of the variable you want to return in the Powershell script, so for example:
$global:test = 4
in Powershell script. In C# after you open the runspace, invoke the policy changer, set up the pipline, you do
var result = runspace.SessionStateProxy.PSVariable.GetValue("test");

string variable_to_return_from_ps_script = "test";
// create Powershell runspace
Runspace runspace = RunspaceFactory.CreateRunspace();
runspace.Open();
//
// here you write the code to invoke the PS script, pipeline, pass parameters etc...
// just like the code you already have
//
// and here's how you retrieve a variable test from PS
var out_var = runspace.SessionStateProxy.PSVariable.GetValue(variable_to_return_from_ps_script);
Console.WriteLine("Variable ${0} value is: ", variable_to_return_from_ps_script);
Console.WriteLine(out_var.ToString());

Related

Execute PowerShell Script from C# MVC Web Application

I need to execute a powershell script from my asp.net MVC Web application. My requirement is to create site collections dynamically. I have the script for it and it works perfectly.There are no arguments which are to be passed to the script. The code which I have been using has been displayed below:
RunspaceConfiguration runspaceConfiguration = RunspaceConfiguration.Create();
Runspace runspace = RunspaceFactory.CreateRunspace(runspaceConfiguration);
runspace.Open();
RunspaceInvoke scriptInvoker = new RunspaceInvoke(runspace);
Pipeline pipeline = runspace.CreatePipeline();
//Here's how you add a new script with arguments
Command myCommand = new Command(scriptfiellocation);
pipeline.Commands.Add(myCommand);
pipeline.Commands.Add("Out-String");
// Execute PowerShell script
var result = pipeline.Invoke();
On executing the code, when I check the count of variable result it gives the count as 1. However on checking my site, there is no site collection that has been created. I am not able to identify where I am going wrong as there is no run time error and the Invoke command also seems to be running properly.
Could anyone tell me where I might be going haywire ? Considering that the PowerShell script works perfectly when running through Management shell.
I had to forego the pipeline approach as I was not able to figure out what the issue was. Also another problem with that approach is that it threw the error: "Get-SPWbTemplate is not recognized as an cmdlet". The following code worked perfectly fine for me and created the required site collections:
PowerShell powershell = PowerShell.Create();
//RunspaceConfiguration runspaceConfiguration = RunspaceConfiguration.Create();
//Runspace runspace = RunspaceFactory.CreateRunspace(runspaceConfiguration)
using (Runspace runspace = RunspaceFactory.CreateRunspace())
{
runspace.Open();
//RunspaceInvoke scriptInvoker = new RunspaceInvoke(runspace);
//scriptInvoker.Invoke("Set-ExecutionPolicy Unrestricted");
powershell.Runspace = runspace;
//powershell.Commands.AddScript("Add-PsSnapin Microsoft.SharePoint.PowerShell");
System.IO.StreamReader sr = new System.IO.StreamReader(scriptfilepath);
powershell.AddScript(sr.ReadToEnd());
//powershell.AddCommand("Out-String");
var results = powershell.Invoke();
if (powershell.Streams.Error.Count > 0)
{
// error records were written to the error stream.
// do something with the items found.
}
}
Also there was no requirement to set the execution policy.
well don't know if its help but i never use pipeline to run Command shell not sure how that work.
But here a quick example
Runspace RS = RunspaceFactory.CreateRunspace(myConnection);
PowerShell PS = PowerShell.Create();
PSCommand PScmd = new PSCommand();
string cmdStr = "Enable-Mailbox -Identity " + username + " -Database DB01 -Alias " + aliasexample;
PScmd.AddScript(cmdStr);
try
{
RS.Open();
PS.Runspace = RS;
PS.Commands = PScmd;
PS.Invoke();
}
catch (Exception ex)
{
ex.ToString();
}
finally
{
RS.Dispose();
RS = null;
PS.Dispose();
PS = null;
}
with the try catch you can catch the error with debugging if something goes wrong.
If i remember correctly i had to put ACL.exe for permission to file system so i can execute the commandshell you can do a quick search on google for it.
Hope this help.

Restarting VM Using Powershell

I am trying to restart a VM using powershell in C#.
First i am trying to run the GET-VM command. It is giving an exception at line:
PSSnapInInfo psinfo = runspaceConfig.AddPSSnapIn("System.Management.Automation", out snapEx);
in below given code. Can someone tell me where i am doing it wrong.
Exception Message : No snap-ins have been registered for Windows PowerShell version 2
My Code :
Command command = new Command("Get-VM");
command.Parameters.Add("Name", "PIE01010299");
RunspaceConfiguration runspaceConfig = RunspaceConfiguration.Create();
PSSnapInException snapEx = null;
PSSnapInInfo psinfo = runspaceConfig.AddPSSnapIn("System.Management.Automation", out snapEx);
Runspace runSpace = RunspaceFactory.CreateRunspace(runspaceConfig);
runSpace.Open();
Pipeline pipeline = runSpace.CreatePipeline();
pipeline.Commands.Add(command);
Collection<PSObject> output = pipeline.Invoke();
runSpace.Close();
foreach (PSObject psObject in output)
{
Console.WriteLine(psObject.ToString());
}
System.Management.Automation is not a snapin. It is the core PowerShell engine assembly. It is loaded by default because your C# project needs to reference that assembly. You probably want to import the Hyper-V module e.g.:
pipeline.Commands.AddCommand("Import-Module").AddArgument("Hyper-V");
pipeline.Invoke();
pipeline.Clear();
Or use the InitialSessionState.ImportPSModule method and then associate that with the runspace.

How to send a string parameter from c# to powershell?

I'm writing 2 apps one with c# and the other with powershell 1.0, in some point of my code I want to pass a string that indicating the server name from my c# app to a powershell script file that I wrote, how do I send it? and how do i accept it?
my code :
RunspaceConfiguration runspaceConfiguration = RunspaceConfiguration.Create();
Runspace runspace = RunspaceFactory.CreateRunspace(runspaceConfiguration);
runspace.Open();
RunspaceInvoke scriptInvoker = new RunspaceInvoke(runspace);
Pipeline pipeline = runspace.CreatePipeline();
String scriptfile = #"c:\test.ps1";
Command myCommand = new Command(scriptfile, false);
CommandParameter testParam = new CommandParameter("username", "serverName");
myCommand.Parameters.Add(testParam);
pipeline.Commands.Add(myCommand);
Collection<PSObject> psObjects;
psObjects = pipeline.Invoke();
runspace.Close();
and my powershell script
param([string]$Username)
write-host $username
What am I missing? I'm kinda new with powershell.
I have machines with PowerShell 2.0 and 3.0 but not 1.0, so my results may differ. When I run your code on my PowerShell 3.0 box, I get:
A command that prompts the user failed because the host program or the
command type does not support user interaction. Try a host program
that supports user interaction, such as the Windows PowerShell Console
or Windows PowerShell ISE, and remove prompt-related commands from
command types that do not support user interaction, such as Windows
PowerShell workflows.
It didn't like the Write-Host, so I changed your script to
param([string]$Username)
Get-Date
Get-ChildItem -Path $userName
Get-Date so that I could see some output without depending on the parameter and GCI to use the parameter. I modified your code to look like this:
RunspaceConfiguration runspaceConfiguration = RunspaceConfiguration.Create();
using (var runspace = RunspaceFactory.CreateRunspace(runspaceConfiguration))
{
runspace.Open();
String scriptfile = #"..\..\..\test.ps1";
String path = #"C:\Users\Public\";
var pipeline = runspace.CreatePipeline();
pipeline.Commands.Add(new Command("Set-ExecutionPolicy RemoteSigned -Scope Process", true));
pipeline.Invoke();
pipeline = runspace.CreatePipeline();
var myCommand = new Command(scriptfile, false);
var testParam = new CommandParameter("username", path);
myCommand.Parameters.Add(testParam);
pipeline.Commands.Add(myCommand);
var psObjects = pipeline.Invoke();
foreach (var obj in psObjects)
{
Console.WriteLine(obj.ToString());
}
runspace.Close();
}
Console.WriteLine("Press a key to continue...");
Console.ReadKey(true);
and it ran without error and displayed the folder contents, on both PoSh 2 and 3.
For info, if you're only setting the execution policy for the current process, you don't need to run elevated, hence I was able to do it in-code.

PowerShell - How to Import-Module in a Runspace

I am trying to create a cmdlet in C#. The code looks something like this:
[Cmdlet(VerbsCommon.Get, "HeapSummary")]
public class Get_HeapSummary : Cmdlet
{
protected override void ProcessRecord()
{
RunspaceConfiguration config = RunspaceConfiguration.Create();
Runspace myRs = RunspaceFactory.CreateRunspace(config);
myRs.Open();
RunspaceInvoke scriptInvoker = new RunspaceInvoke(myRs);
scriptInvoker.Invoke("Set-ExecutionPolicy Unrestricted");
Pipeline pipeline = myRs.CreatePipeline();
pipeline.Commands.Add(#"Import-Module G:\PowerShell\PowerDbg.psm1");
//...
pipeline.Invoke();
Collection<PSObject> psObjects = pipeline.Invoke();
foreach (var psObject in psObjects)
{
WriteObject(psObject);
}
}
}
But trying to execute this CmdLet in PowerShell gives me this error: The term Import-Module is not recognized as the name of a cmdlet. The same command in PowerShell doesn't give me this error. If I execute 'Get-Command' instead, I can see that 'Invoke-Module' is listed as a CmdLet.
Is there a way to do an 'Import-Module' in a Runspace?
Thanks!
There are two ways to import modules programmatically, but I'll address your method first. Your line pipeline.Commands.Add("...") should only be adding the command, not the command AND the parameter. The parameter is added separately:
# argument is a positional parameter
pipeline.Commands.Add("Import-Module");
var command = pipeline.Commands[0];
command.Parameters.Add("Name", #"G:\PowerShell\PowerDbg.psm1")
The above pipeline API is a bit clumsy to use and is informally deprecated for many uses although it's at the base of many of the higher level APIs. The best way to do this in powershell v2 or higher is by using the System.Management.Automation.PowerShell Type and its fluent API:
# if Create() is invoked, a runspace is created for you
var ps = PowerShell.Create(myRS);
ps.Commands.AddCommand("Import-Module").AddArgument(#"g:\...\PowerDbg.psm1")
ps.Invoke()
Another way when using the latter method is to preload modules using InitialSessionState, which avoids the need to seed the runspace explictly with Import-Module.
InitialSessionState initial = InitialSessionState.CreateDefault();
initialSession.ImportPSModule(new[] { modulePathOrModuleName1, ... });
Runspace runspace = RunspaceFactory.CreateRunspace(initial);
runspace.Open();
RunspaceInvoke invoker = new RunspaceInvoke(runspace);
Collection<PSObject> results = invoker.Invoke("...");
Hope this helps.
The simplest way that you can do this is by using AddScript() method.
You can do:
pipeline.AddScript("Import-Module moduleName").Invoke();
If you want to add another import in the same line
pipeline.AddScript("Import-Module moduleName \n Import-Module moduleName2").Invoke();
Its not mandatory to .Invoke() right ofter you add the script to the pipeline, you can add more scripts and invoke later.
pipeline.AddScript("Import-Module moduleName");
pipeline.AddCommand("pwd");
pipeline.Invoke();
For more information visit Microsoft Official website

Running powershell in C#, not having much luck!

I have created a asp.net web application for internal use that allows certain users to start and stop Virtual machines that are linked to there QA testing environments, the code behind page runs a powershell script that starts the selected server once a button is pressed on an ASP.net page.
I have reserched and implimented alot of the code from this site but i am coming up against a few problems.
everytime i click the button on the main web page the error that is fed back from the powershell script says"You cannot call a method on a null-valued expression." the only problem is if i run it from a powershell prompt like this ". \script\test.ps1 'W7EA9'" it works fine.
This is the class that calls the powershell script.
public String Startserver(String Servername)
{
String scriptText =". \\scripts\\test.ps1 " + Servername + "";
// 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);
// execute the script
Collection<PSObject> results = new Collection<PSObject>();
try
{
results = pipeline.Invoke();
}
catch (Exception ex)
{
results.Add(new PSObject((object)ex.Message));
}
// 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();
//return scriptText;
}
and here is the powershell script it is trying to run
Param ($server = $arg[0])
$Core = get-wmiobject -namespace root\virtualization -class Msvm_Computersystem -filter "ElementName = '$server'"
$status = $Core.RequestStateChange(2) `
It may be somthing really obvious but im just not seeing it and any help would be great.
thanks
Chris
Here is a best step-by-step guide to running PowerShell from ASP.NET.
http://devinfra-us.blogspot.com/2011/02/using-powershell-20-from-aspnet-part-1.html
HTH
I don't see where you're providing a parameter to the script anywhere.
i am passing the paramater from a button press on an asp.net page the code behind looks like this
Hypervserver Start = new Hypervserver();
String result = Start.Startserver("W7EA9");
Label1.Visible = true;
Label1.Text = result;
Below is how I ended up doing this.
Runspace runspace = RunspaceFactory.CreateRunspace();
runspace.Open();
Pipeline pipeline = runspace.CreatePipeline();
Command myCommand = new Command("C:\\Scripts\\Test.ps1");
//I used full path name here, not sure if you have to or not
CommandParameter myParam1 = new CommandParameter("-ServerName", "myServer");
myCommand.Parameters.Add(myParam1);
//You can add as many parameters as you need to here
pipeline.Commands.Add(myCommand);
Collection<PSObject> results = pipeline.Invoke();
runspace.Close();
StringBuilder stringBuilder = new StringBuilder()
foreach (PSObject obj in results) {
stringBuilder.AppendLine(obj.ToString());
}
string thestring = stringBuilder.ToString();
A few notes. The scripts first line that is not a comment or blank line should be the parameter list formatted like this:
param([string]$ServerName,[string]$User)
You have this, I just wanted to acknowledge the fact that I could not get this working when my script file was a function with parameters.
For certain commands you may need additional privileges, in my case all of my scripts worked this way except for creating a mailbox for which I had to add credentials onto the connection.
Greg
In powershell, the default arguments collection is called $args, with an 's'; I'm pretty sure that's why $server is null when you run it via code, and thus the Get-WmiObject call returns null, causing the error when you attempt to call the RequestStateChange method on it.
I'm guessing it works fine in your normal powershell window because you already have a $server variable in the session.

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