C# 0 The Complete Reference

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 and 

>

 command-line redirection operators are not part of C#, but are provided by 

the operating system. Thus, if your environment supports I/O redirection (as is the case with 

Windows), you can redirect standard input and standard output without making any changes 

to your program. However, there is a second way that you can redirect the standard streams 

that is under program control. To do so, you will use the 

SetIn( )

,

SetOut( )

, and 

SetError( )

methods, shown here, which are members of 

Console

:

static void SetIn(TextReader 

input

)

static void SetOut(TextWriter 

output

)

static void SetError(TextWriter 

output

)

Thus, to redirect input, call 

SetIn( )

, specifying the desired stream. You can use any input 

stream as long as it is derived from 

TextReader

. To redirect output, call 

SetOut ( )

,

specifying the desired output stream, which must be derived from 

TextWriter

. For example, 

to redirect output to a file, specify a 

FileStream

 that is wrapped in a 

StreamWriter

. The 

following program shows an example:

// Redirect Console.Out.

using System;

using System.IO;

class Redirect {

  static void Main() {

    StreamWriter log_out;

    try {

      log_out = new StreamWriter("logfile.txt");

    }

    catch(IOException exc) {

      Console.WriteLine("Error Opening Log File");

      Console.WriteLine(exc.Message);

      return ;

    }

    // Redirect standard out to logfile.txt.

    Console.SetOut(log_out);

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