Process.OutputDataReceived 事件
定義
重要
部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。
發生於應用程式將某行寫入至其重新導向的 StandardOutput 資料流時。
public:
event System::Diagnostics::DataReceivedEventHandler ^ OutputDataReceived;public event System.Diagnostics.DataReceivedEventHandler? OutputDataReceived;public event System.Diagnostics.DataReceivedEventHandler OutputDataReceived;[System.ComponentModel.Browsable(true)]
public event System.Diagnostics.DataReceivedEventHandler OutputDataReceived;member this.OutputDataReceived : System.Diagnostics.DataReceivedEventHandler [<System.ComponentModel.Browsable(true)>]
member this.OutputDataReceived : System.Diagnostics.DataReceivedEventHandler Public Custom Event OutputDataReceived As DataReceivedEventHandler Public Event OutputDataReceived As DataReceivedEventHandler 事件類型
- 屬性
範例
下列範例說明如何在命令的 ipconfig 重新導向 StandardOutput 資料流程上執行非同步讀取作業。
此範例會建立 OutputHandler 事件處理常式的事件委派，並將它與 OutputDataReceived 事件產生關聯。 事件處理常式會從重新導向 StandardOutput 的資料流程接收文字行、格式化文字，並將它儲存在稍後顯示在範例主控台視窗中的輸出字串中。
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
備註
事件 OutputDataReceived 指出相關聯的 Process 已寫入換行字元 (換行字元 (換行字元， (CR) 、換行字元 (LF) ，或 CR+LF) 重新導向 StandardOutput 資料流程。
事件會在 上的 StandardOutput 非同步讀取作業期間啟用。 若要啟動非同步讀取作業，您必須將 的 Process 資料流程重新導向 StandardOutput 、將事件處理常式新增至 OutputDataReceived 事件，然後呼叫 BeginOutputReadLine 。 之後， OutputDataReceived 每當進程將一行寫入重新導向 StandardOutput 資料流程時，事件就會發出訊號，直到進程結束或呼叫 CancelOutputRead 為止。
注意
正在處理非同步輸出的應用程式應該呼叫 WaitForExit 方法，以確保已清除輸出緩衝區。