Process.OutputDataReceived Événement

Définition

Espace de noms:

System.Diagnostics

Assembly:

System.Diagnostics.Process.dll

Source:

Process.cs

Se produit quand une application écrit dans son flux StandardOutput redirigé.

public:
 event System::Diagnostics::DataReceivedEventHandler ^ OutputDataReceived;

public event System.Diagnostics.DataReceivedEventHandler? OutputDataReceived;

member this.OutputDataReceived : System.Diagnostics.DataReceivedEventHandler 

Public Custom Event OutputDataReceived As DataReceivedEventHandler 

Type d'événement

DataReceivedEventHandler

Exemples

L’exemple suivant montre comment effectuer des opérations de lecture asynchrones sur le flux redirigé StandardOutput de la ipconfig commande.

L’exemple crée un délégué d’événements pour le OutputHandler gestionnaire d’événements et l’associe à l’événement OutputDataReceived . Le gestionnaire d’événements reçoit des lignes de texte du flux redirigé StandardOutput , met en forme le texte et l’enregistre dans une chaîne de sortie qui s’affiche plus tard dans la fenêtre de console de l’exemple.

using namespace System;
using namespace System::IO;
using namespace System::Diagnostics;
using namespace System::Text;

ref class StandardAsyncOutputExample
{
private:
    static int lineCount = 0;
    static StringBuilder^ output = nullptr;

public:
    static void Run()
    {
        Process^ process = gcnew Process();
        process->StartInfo->FileName = "ipconfig.exe";
        process->StartInfo->UseShellExecute = false;
        process->StartInfo->RedirectStandardOutput = true;
        output = gcnew StringBuilder();
        process->OutputDataReceived += gcnew DataReceivedEventHandler(OutputHandler);
        process->Start();

        // Asynchronously read the standard output of the spawned process. 
        // This raises OutputDataReceived events for each line of output.
        process->BeginOutputReadLine();
        process->WaitForExit();

        // Write the redirected output to this application's window.
        Console::WriteLine(output);

        process->WaitForExit();
        process->Close();

        Console::WriteLine("\n\nPress any key to exit");
        Console::ReadLine();
    }

private:
    static void OutputHandler(Object^ sender, DataReceivedEventArgs^ e)
    {
        // Prepend line numbers to each line of the output.
        if (!String::IsNullOrEmpty(e->Data))
        {
            lineCount++;
            output->Append("\n[" + lineCount + "]: " + e->Data);
        }
    }
};

int main()
{
    StandardAsyncOutputExample::Run();
}

using System;
using System.IO;
using System.Diagnostics;
using System.Text;

class StandardAsyncOutputExample
{
    private static int lineCount = 0;
    private static StringBuilder output = new StringBuilder();

    public static void Main()
    {
        Process process = new Process();
        process.StartInfo.FileName = "ipconfig.exe";
        process.StartInfo.UseShellExecute = false;
        process.StartInfo.RedirectStandardOutput = true;
        process.OutputDataReceived += new DataReceivedEventHandler((sender, e) =>
        {
            // Prepend line numbers to each line of the output.
            if (!String.IsNullOrEmpty(e.Data))
            {
                lineCount++;
                output.Append("\n[" + lineCount + "]: " + e.Data);
            }
        });

        process.Start();

        // Asynchronously read the standard output of the spawned process.
        // This raises OutputDataReceived events for each line of output.
        process.BeginOutputReadLine();
        process.WaitForExit();

        // Write the redirected output to this application's window.
        Console.WriteLine(output);

        process.WaitForExit();
        process.Close();

        Console.WriteLine("\n\nPress any key to exit.");
        Console.ReadLine();
    }
}

Imports System.IO
Imports System.Diagnostics
Imports System.Text

Module Module1
    Dim lineCount As Integer = 0
    Dim output As StringBuilder = New StringBuilder()

    Sub Main()
        Dim process As New Process()
        process.StartInfo.FileName = "ipconfig.exe"
        process.StartInfo.UseShellExecute = False
        process.StartInfo.RedirectStandardOutput = True
        AddHandler process.OutputDataReceived, AddressOf OutputHandler
        process.Start()

        ' Asynchronously read the standard output of the spawned process. 
        ' This raises OutputDataReceived events for each line of output.
        process.BeginOutputReadLine()
        process.WaitForExit()

        Console.WriteLine(output)

        process.WaitForExit()
        process.Close()

        Console.WriteLine(Environment.NewLine + Environment.NewLine + "Press any key to exit.")
        Console.ReadLine()
    End Sub

    Sub OutputHandler(sender As Object, e As DataReceivedEventArgs)
        If Not String.IsNullOrEmpty(e.Data) Then
            lineCount += 1

            ' Add the text to the collected output.
            output.Append(Environment.NewLine + "[" + lineCount.ToString() + "]: " + e.Data)
        End If
    End Sub
End Module

Remarques

L’événement OutputDataReceived indique que le associé Process a écrit une ligne qui est terminée par une nouvelle ligne (retour chariot, flux de ligne (LF) ou CR+LF) dans son flux redirigé StandardOutput .

L’événement est activé pendant les opérations de lecture asynchrones sur StandardOutput. Pour démarrer des opérations de lecture asynchrones, vous devez rediriger le StandardOutput flux d’un Process, ajouter votre gestionnaire d’événements à l’événement OutputDataReceived et appeler BeginOutputReadLine. Par la suite, l’événement OutputDataReceived signale chaque fois que le processus écrit une ligne dans le flux redirigé StandardOutput , jusqu’à ce que le processus se termine ou appelle CancelOutputRead.

Notes

L’application qui traite la sortie asynchrone doit appeler la WaitForExit méthode pour s’assurer que la mémoire tampon de sortie a été vidée.

Voir aussi

• RedirectStandardOutput
• StandardOutput
• BeginOutputReadLine()
• CancelOutputRead()
• DataReceivedEventHandler