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Provider cmdlet dynamic parameters

Providers can define dynamic parameters that are added to a provider cmdlet when the user specifies a certain value for one of the static parameters of the cmdlet. For example, a provider can add different dynamic parameters based on what path the user specifies when they call the Get-Item or Set-Item provider cmdlets.

Dynamic Parameter Methods

Dynamic parameters are defined by implementing one of the dynamic parameter methods, such as the System.Management.Automation.Provider.ItemCmdletProvider.GetItemDynamicParameters* and System.Management.Automation.Provider.SetItemDynamicParameters.SetItemDynamicParameters* methods. These methods return an object that has public properties that are decorated with attributes similar to those of stand-alone cmdlets. Here is an example of an implementation of the System.Management.Automation.Provider.ItemCmdletProvider.GetItemDynamicParameters* method taken from the Certificate provider:

protected override object GetItemDynamicParameters(string path)
{
    return new CertificateProviderDynamicParameters();
}

Unlike the static parameters of provider cmdlets, you can specify the characteristics of these parameters in the same way that parameters are defined in stand-alone cmdlets. Here is an example of a dynamic parameter class taken from the Certificate provider:

internal sealed class CertificateProviderDynamicParameters
{
  /// <summary>
  /// Dynamic parameter the controls whether we only return
  /// code signing certs.
  /// </summary>
  [Parameter()]
  public SwitchParameter CodeSigningCert
  {
    get
    {
      {
        return codeSigningCert;
      }
    }

    set
    {
      {
        codeSigningCert = value;
      }
    }
  }

    private SwitchParameter codeSigningCert = new SwitchParameter();
}

Dynamic Parameters

Here is a list of the static parameters that can be used to add dynamic parameters.

See Also

Writing a Windows PowerShell Provider