Exemple StopProcessSample01
Cet exemple montre comment écrire une applet de commande qui demande des commentaires de l’utilisateur avant qu’il tente d’arrêter un processus et comment implémenter un paramètre PassThru indiquant que l’utilisateur souhaite que l’applet de commande retourne un objet. Cette applet de commande est similaire à l’applet de commande Stop-Process fournie par Windows PowerShell 2.0.
Comment générer l’exemple à l’aide de Visual Studio
Une fois le Kit de développement logiciel (SDK) Windows PowerShell 2.0 installé, accédez au dossier StopProcessSample01. L’emplacement par défaut est
C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0\Samples\sysmgmt\WindowsPowerShell\csharp\StopProcessSample01.Double-cliquez sur l’icône du fichier de solution (.sln). L’exemple de projet s’ouvre dans Microsoft Visual Studio.
Dans le menu Générer, sélectionnez Générer la solution pour générer la bibliothèque pour l’exemple dans les dossiers
\binou\bin\debugpar défaut.
Comment exécuter l’exemple
Créez le dossier de module suivant :
[user]\Documents\WindowsPowerShell\Modules\StopProcessSample01Copiez l’exemple d’assembly dans le dossier du module.
Démarrez Windows PowerShell.
Exécutez la commande suivante pour charger l’assembly dans Windows PowerShell :
Import-Module stopprossessample01Exécutez la commande suivante pour exécuter l’applet de commande :
Stop-Proc
Spécifications
Cet exemple nécessite Windows PowerShell 2.0.
Montre ce qui suit
Cet exemple illustre ce qui suit.
Déclaration d’une classe d’applet de commande à l’aide de l’attribut Cmdlet.
Déclaration de paramètres d’applet de commande à l’aide de l’attribut Parameter.
Appel de la méthode ShouldProcess pour demander la confirmation.
Implémentation d’un paramètre
PassThruqui indique si l’utilisateur souhaite que l’applet de commande retourne un objet. Par défaut, cette applet de commande ne retourne pas d’objet au pipeline.
Exemple :
Cet exemple montre comment implémenter un paramètre PassThru qui indique que l’utilisateur souhaite que l’applet de commande retourne un objet, et comment demander des commentaires utilisateur en appelant les méthodes ShouldProcess et ShouldContinue.
using System;
using System.Diagnostics;
using System.Collections;
using Win32Exception = System.ComponentModel.Win32Exception;
using System.Management.Automation; // Windows PowerShell namespace
using System.Globalization;
namespace Microsoft.Samples.PowerShell.Commands
{
#region StopProcCommand
/// <summary>
/// This class implements the Stop-Proc cmdlet.
/// </summary>
[Cmdlet(VerbsLifecycle.Stop, "Proc",
SupportsShouldProcess = true)]
public class StopProcCommand : Cmdlet
{
#region Parameters
/// <summary>
/// This parameter provides the list of process names on
/// which the Stop-Proc cmdlet will work.
/// </summary>
[Parameter(
Position = 0,
Mandatory = true,
ValueFromPipeline = true,
ValueFromPipelineByPropertyName = true
)]
public string[] Name
{
get { return processNames; }
set { processNames = value; }
}
private string[] processNames;
/// <summary>
/// This parameter overrides the ShouldContinue call to force
/// the cmdlet to stop its operation. This parameter should always
/// be used with caution.
/// </summary>
[Parameter]
public SwitchParameter Force
{
get { return force; }
set { force = value; }
}
private bool force;
/// <summary>
/// This parameter indicates that the cmdlet should return
/// an object to the pipeline after the processing has been
/// completed.
/// </summary>
[Parameter]
public SwitchParameter PassThru
{
get { return passThru; }
set { passThru = value; }
}
private bool passThru;
#endregion Parameters
#region Cmdlet Overrides
/// <summary>
/// The ProcessRecord method does the following for each of the
/// requested process names:
/// 1) Check that the process is not a critical process.
/// 2) Attempt to stop that process.
/// If no process is requested then nothing occurs.
/// </summary>
protected override void ProcessRecord()
{
foreach (string name in processNames)
{
// For every process name passed to the cmdlet, get the associated
// processes.
// Write a non-terminating error for failure to retrieve
// a process.
Process[] processes;
try
{
processes = Process.GetProcessesByName(name);
}
catch (InvalidOperationException ioe)
{
WriteError(new ErrorRecord(ioe,"UnableToAccessProcessByName",
ErrorCategory.InvalidOperation, name));
continue;
}
// Try to stop the processes that have been retrieved.
foreach (Process process in processes)
{
string processName;
try
{
processName = process.ProcessName;
}
catch (Win32Exception e)
{
WriteError(new ErrorRecord(e, "ProcessNameNotFound",
ErrorCategory.ReadError, process));
continue;
}
// Confirm the operation with the user first.
// This is always false if the WhatIf parameter is set.
if (!ShouldProcess(string.Format(CultureInfo.CurrentCulture,"{0} ({1})", processName,
process.Id)))
{
continue;
}
// Make sure that the user really wants to stop a critical
// process that could possibly stop the computer.
bool criticalProcess =
criticalProcessNames.Contains(processName.ToLower(CultureInfo.CurrentCulture));
if (criticalProcess &&!force)
{
string message = String.Format
(CultureInfo.CurrentCulture,
"The process \"{0}\" is a critical process and should not be stopped. Are you sure you wish to stop the process?",
processName);
// It is possible that the ProcessRecord method is called
// multiple times when objects are received as inputs from
// the pipeline. So to retain YesToAll and NoToAll input that
// the user may enter across multiple calls to this function,
// they are stored as private members of the cmdlet.
if (!ShouldContinue(message, "Warning!",
ref yesToAll, ref noToAll))
{
continue;
}
} // if (criticalProcess...
// Stop the named process.
try
{
process.Kill();
}
catch (Exception e)
{
if ((e is Win32Exception) || (e is SystemException) ||
(e is InvalidOperationException))
{
// This process could not be stopped so write
// a non-terminating error.
WriteError(new ErrorRecord(e, "CouldNotStopProcess",
ErrorCategory.CloseError, process));
continue;
} // if ((e is...
else throw;
} // catch
// If the PassThru parameter is
// specified, return the terminated process.
if (passThru)
{
WriteObject(process);
}
} // foreach (Process...
} // foreach (string...
} // ProcessRecord
#endregion Cmdlet Overrides
#region Private Data
private bool yesToAll, noToAll;
/// <summary>
/// Partial list of critical processes that should not be
/// stopped. Lower case is used for case insensitive matching.
/// </summary>
private ArrayList criticalProcessNames = new ArrayList(
new string[] { "system", "winlogon", "spoolsv" }
);
#endregion Private Data
} // StopProcCommand
#endregion StopProcCommand
}
