Console.SetOut(TextWriter) 方法

定义

Out 属性设置为面向 TextWriter 对象。Sets the Out property to target the TextWriter object.

public:
 static void SetOut(System::IO::TextWriter ^ newOut);
public static void SetOut (System.IO.TextWriter newOut);
static member SetOut : System.IO.TextWriter -> unit
Public Shared Sub SetOut (newOut As TextWriter)

参数

newOut
TextWriter

要用作新的标准输出的文本编写器。A text writer to be used as the new standard output.

异常

newOutnullnewOut is null.

调用方没有所要求的权限。The caller does not have the required permission.

示例

下面的示例演示 SetOut 方法的用法。The following example illustrates the use of the SetOut method. 它用制表符替换字符串中的四个连续空格字符。It replaces four consecutive space characters in a string with a tab character. 若要运行此命令,必须提供两个命令行参数。To run it, you must supply two command line arguments. 第一个是要将标准输入流重定向到的现有文本文件的名称。The first is the name of an existing text file to redirect the standard input stream to. 第二个是要将标准输出流重定向到的文件的名称。The second is the name of a file to redirect the standard output stream to. 此文件不需要存在。This file need not exist. 如果它这么做,其内容将被覆盖。If it does, its contents will be overwritten.

using namespace System;
using namespace System::IO;

int main()
{
   array<String^>^args = Environment::GetCommandLineArgs();
   const int tabSize = 4;
   String^ usageText = "Usage: INSERTTABS inputfile.txt outputfile.txt";
   StreamWriter^ writer = nullptr;
   if ( args->Length < 3 )
   {
      Console::WriteLine( usageText );
      return 1;
   }

   try
   {
      // Attempt to open output file.
      writer = gcnew StreamWriter( args[ 2 ] );
      // Redirect standard output from the console to the output file.
      Console::SetOut( writer );
      // Redirect standard input from the console to the input file.
      Console::SetIn( gcnew StreamReader( args[ 1 ] ) );
   }
   catch ( IOException^ e ) 
   {
      TextWriter^ errorWriter = Console::Error;
      errorWriter->WriteLine( e->Message );
      errorWriter->WriteLine( usageText );
      return 1;
   }

   String^ line;
   while ( (line = Console::ReadLine()) != nullptr )
   {
      String^ newLine = line->Replace( ((String^)"")->PadRight( tabSize, ' ' ), "\t" );
      Console::WriteLine( newLine );
   }

   writer->Close();
   
   // Recover the standard output stream so that a 
   // completion message can be displayed.
   StreamWriter^ standardOutput = gcnew StreamWriter( Console::OpenStandardOutput() );
   standardOutput->AutoFlush = true;
   Console::SetOut( standardOutput );
   Console::WriteLine( "INSERTTABS has completed the processing of {0}.", args[ 1 ] );
   return 0;
}

using System;
using System.IO;

public class InsertTabs
{
    private const int tabSize = 4;
    private const string usageText = "Usage: INSERTTABS inputfile.txt outputfile.txt";
    public static int Main(string[] args)
    {
        if (args.Length < 2)
        {
            Console.WriteLine(usageText);
            return 1;
        }

        try
        {
            // Attempt to open output file.
            using (var writer = new StreamWriter(args[1]))
            {
                using (var reader = new StreamReader(args[0]))
                {
                    // Redirect standard output from the console to the output file.
                    Console.SetOut(writer);
                    // Redirect standard input from the console to the input file.
                    Console.SetIn(reader);
                    string line;
                    while ((line = Console.ReadLine()) != null)
                    {
                        string newLine = line.Replace(("").PadRight(tabSize, ' '), "\t");
                        Console.WriteLine(newLine);
                    }
                }
            }
        }
        catch(IOException e)
        {
            TextWriter errorWriter = Console.Error;
            errorWriter.WriteLine(e.Message);
            errorWriter.WriteLine(usageText);
            return 1;
        }

        // Recover the standard output stream so that a 
        // completion message can be displayed.
        var standardOutput = new StreamWriter(Console.OpenStandardOutput());
        standardOutput.AutoFlush = true;
        Console.SetOut(standardOutput);
        Console.WriteLine($"INSERTTABS has completed the processing of {args[0]}.");
        return 0;
    }
}
Imports System.IO

Public Module InsertTabs
    Private Const tabSize As Integer = 4
    Private Const usageText As String = "Usage: INSERTTABS inputfile.txt outputfile.txt"
   
    Public Function Main(args As String()) As Integer
        If args.Length < 2 Then
            Console.WriteLine(usageText)
            Return 1
        End If
      
        Try
            ' Attempt to open output file.
            Using writer As New StreamWriter(args(1))
                Using reader As New StreamReader(args(0))
                    ' Redirect standard output from the console to the output file.
                    Console.SetOut(writer)
                    ' Redirect standard input from the console to the input file.
                    Console.SetIn(reader)
                    Dim line As String = Console.ReadLine()
                    While line IsNot Nothing
                        Dim newLine As String = line.Replace("".PadRight(tabSize, " "c), ControlChars.Tab)
                        Console.WriteLine(newLine)
                        line = Console.ReadLine()
                    End While
                End Using
            End Using
        Catch e As IOException
            Dim errorWriter As TextWriter = Console.Error
            errorWriter.WriteLine(e.Message)
            errorWriter.WriteLine(usageText)
            Return 1
        End Try

        ' Recover the standard output stream so that a 
        ' completion message can be displayed.
        Dim standardOutput As New StreamWriter(Console.OpenStandardOutput())
        standardOutput.AutoFlush = True
        Console.SetOut(standardOutput)
        Console.WriteLine($"INSERTTABS has completed the processing of {args(0)}.")
        Return 0
    End Function 
End Module

注解

默认情况下,Out 属性设置为标准输出流。By default, the Out property is set to the standard output stream.

封装 FileStreamStreamWriter 可用于将输出发送到文件。A StreamWriter that encapsulates a FileStream can be used to send output to a file. 例如:For example:

Console::WriteLine("Hello World");
FileStream^ fs = gcnew FileStream("Test.txt", FileMode::Create);
// First, save the standard output.
TextWriter^ tmp = Console::Out;
StreamWriter^ sw = gcnew StreamWriter(fs);
Console::SetOut(sw);
Console::WriteLine("Hello file");
Console::SetOut(tmp);
Console::WriteLine("Hello World");
sw->Close();
Console.WriteLine("Hello World");
FileStream fs = new FileStream("Test.txt", FileMode.Create);
// First, save the standard output.
TextWriter tmp = Console.Out;
StreamWriter sw = new StreamWriter(fs);
Console.SetOut(sw);
Console.WriteLine("Hello file");
Console.SetOut(tmp);
Console.WriteLine("Hello World");
sw.Close();
Console.WriteLine("Hello World")
Dim fs As New FileStream("Test.txt", FileMode.Create)
' First, save the standard output.
Dim tmp as TextWriter = Console.Out
Dim sw As New StreamWriter(fs)
Console.SetOut(sw)
Console.WriteLine("Hello file")
Console.SetOut(tmp)
Console.WriteLine("Hello World")
sw.Close()

Out 返回的实际对象可能是所提供的文本编写器周围的同步包装。The actual object returned by Out may be a synchronized wrapper around the provided text writer.

适用于

另请参阅