StopProcessSample01 – exempel

Det här exemplet visar hur du skriver en cmdlet som begär feedback från användaren innan den försöker stoppa en process och hur du implementerar en PassThru parameter som anger att cmdleten ska returnera ett objekt. Denna cmdlet liknar den Stop-Process cmdlet som tillhandahålls av Windows PowerShell 2,0.

Så här skapar du exemplet med hjälp av Visual Studio.

  1. Med Windows PowerShell 2,0 SDK installerat navigerar du till mappen StopProcessSample01 Standard platsen är C:\Program Files (x86) \Microsoft SDKs\Windows\v7.0\Samples\sysmgmt\WindowsPowerShell\csharp\StopProcessSample01.

  2. Dubbelklicka på ikonen för lösnings filen (. SLN). Detta öppnar exempelprojektet i Microsoft Visual Studio.

  3. I menyn build väljer du build-lösning.

    Biblioteket för exemplet skapas i standardmappen \Bin eller \Bin\Debug.

Köra exemplet

  1. Skapa följande modul-mapp:

    [user]/documents/windowspowershell/modules/StopProcessSample01

  2. Kopiera exempel sammansättningen till module-mappen.

  3. Starta Windows PowerShell

  4. Kör följande kommando för att läsa in sammansättningen i Windows PowerShell:

    import-module stopprossessample01

  5. Kör följande kommando för att köra cmdleten:

    stop-proc

Krav

Det här exemplet kräver Windows PowerShell 2,0.

Demonstrationer

Det här exemplet demonstrerar följande.

  • Deklarera en cmdlet-klass med hjälp av cmdlet-attributet.

  • Deklarera en cmdlet-parameter genom att använda attributet parameter.

  • Anropar ShouldProcess-metoden för att begära bekräftelse.

  • Implementera en PassThru parameter som anger om användaren vill att cmdleten ska returnera ett objekt. Som standard returnerar denna cmdlet inget objekt till pipelinen.

Exempel

Det här exemplet visar hur du implementerar en PassThru parameter som anger att en-cmdlet ska returnera ett objekt och hur du begär feedback via anrop till ShouldProcess ShouldContinue metoderna och.

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 nonterminating 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 nonterminating 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
}

Se även

Skriva en Windows PowerShell-cmdlet