Process.OutputDataReceived Evento

Definición

Espacio de nombres:

System.Diagnostics

Ensamblado:

System.Diagnostics.Process.dll

Source:

Process.cs

Se produce cada vez que una aplicación escribe una línea en su secuencia StandardOutput redirigida.

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

public event System.Diagnostics.DataReceivedEventHandler? OutputDataReceived;

member this.OutputDataReceived : System.Diagnostics.DataReceivedEventHandler 

Public Custom Event OutputDataReceived As DataReceivedEventHandler 

Tipo de evento

DataReceivedEventHandler

Ejemplos

En el ejemplo siguiente se muestra cómo realizar operaciones de lectura asincrónicas en el flujo redirigido StandardOutput del ipconfig comando.

En el ejemplo se crea un delegado de eventos para el OutputHandler controlador de eventos y se asocia al OutputDataReceived evento. El controlador de eventos recibe líneas de texto de la secuencia redirigida StandardOutput , da formato al texto y lo guarda en una cadena de salida que se muestra más adelante en la ventana de la consola del ejemplo.

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

Comentarios

El OutputDataReceived evento indica que el asociado Process ha escrito una línea terminada con una nueva línea (retorno de carro (CR), avance de línea (LF) o CR+LF) en su secuencia redirigida StandardOutput .

El evento se habilita durante las operaciones de lectura asincrónicas en StandardOutput. Para iniciar operaciones de lectura asincrónicas, debe redirigir la StandardOutput secuencia de un Process, agregar el controlador de eventos al evento y llamar a OutputDataReceivedBeginOutputReadLine. A partir de entonces, el OutputDataReceived evento señala cada vez que el proceso escribe una línea en la secuencia redirigida StandardOutput , hasta que el proceso sale o llama a CancelOutputRead.

Nota

La aplicación que procesa la salida asincrónica debe llamar al WaitForExit método para asegurarse de que se ha vaciado el búfer de salida.

Consulte también

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