Task.Factory Proprietà

Definizione

Fornisce l'accesso ai metodi factory per la creazione e la configurazione delle istanze di Task e Task<TResult>.Provides access to factory methods for creating and configuring Task and Task<TResult> instances.

public:
 static property System::Threading::Tasks::TaskFactory ^ Factory { System::Threading::Tasks::TaskFactory ^ get(); };
public static System.Threading.Tasks.TaskFactory Factory { get; }
member this.Factory : System.Threading.Tasks.TaskFactory
Public Shared ReadOnly Property Factory As TaskFactory

Valore della proprietà

Oggetto factory in grado di creare una vasta gamma di oggetti Task e Task<TResult>.A factory object that can create a variety of Task and Task<TResult> objects.

Commenti

Questa proprietà restituisce un'istanza predefinita della classe TaskFactory identica a quella creata chiamando il costruttore di TaskFactory.TaskFactory() senza parametri.This property returns a default instance of the TaskFactory class that is identical to the one created by calling the parameterless TaskFactory.TaskFactory() constructor. Dispone dei valori di proprietà seguenti:It has the following property values:

ProprietàProperty ValoreValue
TaskFactory.CancellationToken CancellationToken.None
TaskFactory.ContinuationOptions TaskContinuationOptions.None
TaskFactory.CreationOptions TaskCreationOptions.None
TaskFactory.Scheduler nullo TaskScheduler.Currentnull, or TaskScheduler.Current

L'uso più comune di questa proprietà consiste nel creare e avviare una nuova attività in una singola chiamata al metodo TaskFactory.StartNew.The most common use of this property is to create and start a new task in a single call to the TaskFactory.StartNew method.

Nota

A partire dalla .NET Framework 4.5.NET Framework 4.5, il metodo Task.Run fornisce il modo più semplice per creare un oggetto Task con i valori di configurazione predefiniti.Starting with the .NET Framework 4.5.NET Framework 4.5, the Task.Run method provides the easiest way to create a Task object with default configuration values.

Nell'esempio seguente viene utilizzata la proprietà Factory statica per effettuare due chiamate al metodo TaskFactory.StartNew.The following example uses the static Factory property to make two calls to the TaskFactory.StartNew method. Il primo compila una matrice con i nomi dei file nella directory documenti dell'utente, mentre la seconda compila una matrice con i nomi delle sottodirectory della directory documenti dell'utente.The first populates an array with the names of files in the user's MyDocuments directory, while the second populates an array with the names of subdirectories of the user's MyDocuments directory. Viene quindi chiamato il metodo TaskFactory.ContinueWhenAll(Task[], Action<Task[]>), che visualizza informazioni sul numero di file e directory nelle due matrici dopo che le prime due attività hanno completato l'esecuzione.It then calls the TaskFactory.ContinueWhenAll(Task[], Action<Task[]>) method, which displays information about the number of files and directories in the two arrays after the first two tasks have completed execution.

using System;
using System.IO;
using System.Threading.Tasks;

public class Example
{
   public static void Main()
   {
      Task[] tasks = new Task[2];
      String[] files = null;
      String[] dirs = null;
      String docsDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);

      tasks[0] = Task.Factory.StartNew( () => files = Directory.GetFiles(docsDirectory));
      tasks[1] = Task.Factory.StartNew( () => dirs = Directory.GetDirectories(docsDirectory));

      Task.Factory.ContinueWhenAll(tasks, completedTasks => {
                                             Console.WriteLine("{0} contains: ", docsDirectory);
                                             Console.WriteLine("   {0} subdirectories", dirs.Length);
                                             Console.WriteLine("   {0} files", files.Length);
                                          } );
   }
}
// The example displays output like the following:
//       C:\Users\<username>\Documents contains:
//          24 subdirectories
//          16 files
Imports System.IO
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim tasks(1) As Task
      Dim files() As String = Nothing
      Dim dirs() As String = Nothing
      Dim docsDirectory As String = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
      
      tasks(0) = Task.Factory.StartNew( Sub()
                                           files = Directory.GetFiles(docsDirectory)
                                        End Sub )
      tasks(1) = Task.Factory.StartNew( Sub()
                                           dirs = Directory.GetDirectories(docsDirectory)
                                        End Sub )
      Task.Factory.ContinueWhenAll(tasks, Sub(completedTasks)
                                             Console.WriteLine("{0} contains: ", docsDirectory)
                                             Console.WriteLine("   {0} subdirectories", dirs.Length)
                                             Console.WriteLine("   {0} files", files.Length)
                                          End Sub)
   End Sub
End Module
' The example displays output like the following:
'       C:\Users\<username>\Documents contains:
'          24 subdirectories
'          16 files

Si applica a

Vedi anche