Set Cmdlet

Saat merancang cmdlet, Anda mungkin mengalami kasus di mana Anda perlu melakukan beberapa tindakan pada bagian data yang sama. Misalnya, Anda mungkin perlu mendapatkan dan mengatur data atau memulai dan menghentikan proses. Meskipun Anda harus membuat cmdlet terpisah untuk melakukan setiap tindakan, desain cmdlet Anda harus menyertakan kelas dasar tempat kelas untuk cmdlet individu diturunkan.

Ingatlah hal-hal berikut saat menerapkan kelas dasar.

• Deklarasikan parameter umum yang digunakan oleh semua cmdlet turunan di kelas dasar.

• Tambahkan parameter khusus cmdlet ke kelas cmdlet yang sesuai.

• Ambil alih metode pemrosesan input yang sesuai di kelas dasar.

• Deklarasikan atribut System.Management.Automation.CmdletAttribute pada semua kelas cmdlet, tetapi jangan mendeklarasikannya di kelas dasar.

• Terapkan System.Management.Automation.PSSnapIn atau System.Management.Automation.CustomPSSnapIn kelas yang namanya dan deskripsinya mencerminkan kumpulan cmdlet.

Contoh

Contoh berikut menunjukkan implementasi kelas dasar yang digunakan oleh cmdlet Get-Proc dan Stop-Proc yang berasal dari kelas dasar yang sama.

using System;
using System.Diagnostics;
using System.Management.Automation;             //Windows PowerShell namespace.

namespace Microsoft.Samples.PowerShell.Commands
{

  #region ProcessCommands

  /// <summary>
  /// This class implements a Stop-Proc cmdlet. The parameters
  /// for this cmdlet are defined by the BaseProcCommand class.
  /// </summary>
  [Cmdlet(VerbsLifecycle.Stop, "Proc", SupportsShouldProcess = true)]
  public class StopProcCommand : BaseProcCommand
  {
    public override void ProcessObject(Process process)
    {
      if (ShouldProcess(process.ProcessName, "Stop-Proc"))
      {
        process.Kill();
      }
    }
  }

  /// <summary>
  /// This class implements a Get-Proc cmdlet. The parameters
  /// for this cmdlet are defined by the BaseProcCommand class.
  /// </summary>

  [Cmdlet(VerbsCommon.Get, "Proc")]
  public class GetProcCommand : BaseProcCommand
  {
    public override void ProcessObject(Process process)
    {
      WriteObject(process);
    }
  }

  /// <summary>
  /// This class is the base class that defines the common
  /// functionality used by the Get-Proc and Stop-Proc
  /// cmdlets.
  /// </summary>
  public class BaseProcCommand : Cmdlet
  {
    #region Parameters

    // Defines the Name parameter that is used to
    // specify a process by its name.
    [Parameter(
               Position = 0,
               Mandatory = true,
               ValueFromPipeline = true,
               ValueFromPipelineByPropertyName = true
    )]
    public string[] Name
    {
      get { return processNames; }
      set { processNames = value; }
    }
    private string[] processNames;

    // Defines the Exclude parameter that is used to
    // specify which processes should be excluded when
    // the cmdlet performs its action.
    [Parameter()]
    public string[] Exclude
    {
      get { return excludeNames; }
      set { excludeNames = value; }
    }
    private string[] excludeNames = new string[0];
    #endregion Parameters

    public virtual void ProcessObject(Process process)
    {
      throw new NotImplementedException("This method should be overridden.");
    }

    #region Cmdlet Overrides
    // <summary>
    // For each of the requested process names, retrieve and write
    // the associated processes.
    // </summary>
    protected override void ProcessRecord()
    {
      // Set up the wildcard characters used in resolving
      // the process names.
      WildcardOptions options = WildcardOptions.IgnoreCase |
                                WildcardOptions.Compiled;

      WildcardPattern[] include = new WildcardPattern[Name.Length];
      for (int i = 0; i < Name.Length; i++)
      {
        include[i] = new WildcardPattern(Name[i], options);
      }

      WildcardPattern[] exclude = new WildcardPattern[Exclude.Length];
      for (int i = 0; i < Exclude.Length; i++)
      {
        exclude[i] = new WildcardPattern(Exclude[i], options);
      }

      foreach (Process p in Process.GetProcesses())
      {
        foreach (WildcardPattern wIn in include)
        {
          if (wIn.IsMatch(p.ProcessName))
          {
            bool processThisOne = true;
            foreach (WildcardPattern wOut in exclude)
            {
              if (wOut.IsMatch(p.ProcessName))
              {
                processThisOne = false;
                break;
              }
            }
            if (processThisOne)
            {
              ProcessObject(p);
            }
            break;
          }
        }
      }
    }
    #endregion Cmdlet Overrides
  }
    #endregion ProcessCommands
}

Lihat Juga

Menulis Cmdlet Windows PowerShell