Console.SetError(TextWriter) Method

public:
 static void SetError(System::IO::TextWriter ^ newError);

public static void SetError(System.IO.TextWriter newError);

static member SetError : System.IO.TextWriter -> unit

Public Shared Sub SetError (newError As TextWriter)

Parameters

Exceptions

Examples

The following example shows how to redirect the standard error stream to a file.

using System;
using System.IO;
using System.Reflection;

public class RedirectStdErr
{
 public static void Main()
 {
 // Define file to receive error stream.
 DateTime appStart = DateTime.Now;
 string fn = @"c:\temp\errlog" + appStart.ToString("yyyyMMddHHmm") + ".log";
 TextWriter errStream = new StreamWriter(fn);
 string appName = typeof(RedirectStdErr).Assembly.Location;
 appName = appName.Substring(appName.LastIndexOf('\\') + 1);
 // Redirect standard error stream to file.
 Console.SetError(errStream);
 // Write file header.
 Console.Error.WriteLine("Error Log for Application {0}", appName);
 Console.Error.WriteLine();
 Console.Error.WriteLine("Application started at {0}.", appStart);
 Console.Error.WriteLine();
 //
 // Application code along with error output
 //
 // Close redirected error stream.
 Console.Error.Close();
 }
}

open System
open System.IO
open System.Reflection

[<EntryPoint>]
let main _ =
 // Define file to receive error stream.
 let appStart = DateTime.Now
 let fn = @"C:\temp\errlog" + appStart.ToString "yyyyMMddHHmm" + ".log"
 use fs = new FileStream(fn, FileMode.OpenOrCreate)
 let errStream = new StreamWriter(fs)
 let appName = 
 let appName = Assembly.GetExecutingAssembly().Location
 appName.Substring(appName.LastIndexOf('\\') + 1)

 // Redirect standard error stream to file.
 Console.SetError errStream

 // Write file header.
 Console.Error.WriteLine $"Error Log for Application {appName}"
 Console.Error.WriteLine()
 Console.Error.WriteLine $"Application started at {appStart}."
 Console.Error.WriteLine()
 //
 // Application code along with error output
 //
 // Close redirected error stream.
 Console.Error.Close()
 
 0

Imports System.IO
Imports System.Reflection

Module RedirectStdErr
 Public Sub Main()
 ' Define file to receive error stream.
 Dim appStart As Date = Date.Now
 Dim fn As String = "c:\temp\errlog" & appStart.ToString("yyyyMMddHHmm") & ".log"
 Dim errStream As New StreamWriter(fn)
 Dim appName As String = GetType(RedirectStdErr).Assembly.Location
 appName = Mid(appName, InStrRev(appName, "\") + 1)
 ' Redirect standard error stream to file.
 Console.SetError(errStream)
 ' Write file header.
 Console.Error.WriteLine("Error Log for Application {0}", appName)
 Console.Error.WriteLine()
 Console.Error.WriteLine("Application started at {0}.", appStart)
 Console.Error.WriteLine()
 '
 ' Application code along with error output 
 '
 ' Close redirected error stream.
 Console.Error.Close()
 End Sub
End Module

Remarks

By default, the Error property is set to the standard error output stream.

A StreamWriter that encapsulates a FileStream can be used to send error messages to a file.

See also

• IsErrorRedirected
• Error