Process.OutputDataReceived Kejadian

Definisi

Ruang nama:

System.Diagnostics

Rakitan:

netstandard.dll, System.Diagnostics.Process.dll

Sumber:

Process.cs

Terjadi setiap kali aplikasi menulis baris ke aliran StandardOutput yang dialihkan.

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

public event System.Diagnostics.DataReceivedEventHandler? OutputDataReceived;

member this.OutputDataReceived : System.Diagnostics.DataReceivedEventHandler 

Public Custom Event OutputDataReceived As DataReceivedEventHandler 

Jenis Acara

DataReceivedEventHandler

Contoh

Contoh berikut mengilustrasikan cara melakukan operasi baca asinkron pada aliran perintah yang StandardOutput dialihkanipconfig.

Contoh membuat delegasi peristiwa untuk OutputHandler penanganan aktivitas dan mengaitkannya dengan OutputDataReceived peristiwa. Penanganan aktivitas menerima baris teks dari aliran yang dialihkan StandardOutput , memformat teks, dan menyimpannya dalam string output yang kemudian ditampilkan di jendela konsol contoh.

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();
    }
}

open System
open System.Diagnostics
open System.Text

let mutable lineCount = 0
let output = StringBuilder()

let proc = new Process()
proc.StartInfo.FileName <- "ipconfig.exe"
proc.StartInfo.UseShellExecute <- false
proc.StartInfo.RedirectStandardOutput <- true

proc.OutputDataReceived.AddHandler(
    DataReceivedEventHandler(fun _ e ->
        // Prepend line numbers to each line of the output.
        if not (String.IsNullOrEmpty e.Data) then
            lineCount <- lineCount + 1
            output.Append $"\n[{lineCount}]: {e.Data}" |> ignore)
)


proc.Start() |> ignore

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

// Write the redirected output to this application's window.
printfn $"{output}"

proc.WaitForExit()
proc.Close()

printfn "\n\nPress any key to exit."
stdin.ReadLine() |> ignore

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

Keterangan

Peristiwa menunjukkan OutputDataReceived bahwa yang terkait Process telah menulis baris yang dihentikan dengan baris baru (carriage return (CR), line feed (LF), atau CR+LF) ke aliran yang dialihkan StandardOutput .

Peristiwa ini juga dimunculkan ketika akhir aliran yang dialihkan tercapai. Dalam hal ini, Data properti penanganan DataReceivedEventArgs aktivitas adalah null.

Peristiwa diaktifkan selama operasi baca asinkron pada StandardOutput. Untuk memulai operasi baca asinkron, Anda harus mengalihkan StandardOutput aliran Process, menambahkan penanganan aktivitas Anda ke OutputDataReceived peristiwa, dan memanggil BeginOutputReadLine. Setelah itu, peristiwa memberi OutputDataReceived sinyal setiap kali proses menulis baris ke aliran yang dialihkan StandardOutput , sampai proses keluar atau memanggil CancelOutputRead.

Note

Aplikasi yang memproses output asinkron harus memanggil WaitForExit metode untuk memastikan bahwa buffer output telah dibersihkan.

Lihat juga

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