How to capture console output from a service C#?

Question

We have a C# service that is deployed to a remote customer system. The application writes a substantial amount of \"diagnostic\" information to the console (i.e. Console.WriteL

Answer 1

You've got a bunch of options; redirecting console output to a file and using a proper logging library as mentioned are two good ones. Here's a middle option: write to the event log.

EventLog log;
string logsource = "MyService";

// execute once per invocation
if (!System.Diagnostics.EventLog.SourceExists(logsource))
{
    System.Diagnostics.EventLog.CreateEventSource(
        logsource, "Application");
}
log = new EventLog();
log.Source = logsource;
log.Log = "Application";

// replace console logging with this
log.WriteEntry(message, EventLogEntryType.Information);

Then look for entries in the Application event log (Administrative Tools -> Event Viewer) where Source = "MyService".

Answer 2

use debug.writeline and use sysinternals debugview?

Answer 3

Are you able to change the service code at all? If so, using Console.SetOut to write to a file instead would be the most obvious first port of call. Then change to using a proper logging library for the next release :)

Answer 4

In general, you should avoid writing diagnostic information directly to Console, the Event Log, MSMQ or elsewhere from your application code. Instead call a logging API, and use configuration to redirect the output wherever you want.

For example, you could replace all the Console.WriteLine by Trace.WriteLine (*). Then you can redirect output to the console, a file or elsewhere by modifying the application configuration file: for example to output to the console, use a ConsoleTraceListener, something like:

<configuration>
  <system.diagnostics>
    <trace autoflush="false" indentsize="4">
      <listeners>
        <add name="configConsoleListener"
             type="System.Diagnostics.ConsoleTraceListener" />
      </listeners>
    </trace>
  </system.diagnostics>
 </configuration>

While debugging, you'll get your output on the console - on the customer site you'd configure it to redirect the trace output to a file, to the event log or similar.

Even better, use a 3rd party logging framework (I'd recommend Log4Net) which will give you more options than System.Diagnostics.Trace.

(*) Trace.Write/Trace.WriteLine are the same as Debug.Write/Debug.WriteLine, except that the latter are only compiled if the DEBUG symbol is defined. So prefer Trace to Debug if you want the output to be available in Release builds.

Answer 5

I wouldn't use Console.WriteLine at all from a Window Service. You should probably log these errors to a log file.

Another way of doing this so that multiple applications can consume the logs is posting the log messages to a MSMQ queue.

Answer 6

I found this post on MSDN which binds the Console output to a rich text box, worked for me very quickly and easily.

It overrides WriteLine, and could be expanded to override other methods.