A simple color ConsoleTraceListener
Considering how many pre-release Whidbey demos I saw showing off the new color support in Console applications, I'm surprised this wasn't include in the box. I use a System.Diagnostics.TraceSource coupled with the ConsoleTraceListener for output in console apps. Of course, when you have verbose logging enabled, you see a LOT of gray text scroll across the screen, and nothing really stands out. Reminds me of trying to decode NAnt output after living with MSBuild for a while. I did a quick search for "color consoletracelistener" and came across this offering from Mauricio Rojas. I (probably unfairly) dimissed it because it looked much more complicated than I would expect (ok, and because it was in VB).So I spent 10 minutes throwing this together. It works for every scenario that I need. In other words, I make no claims that it is general purpose solution for you - it may not add color to every type of trace message (depending on which methods you use to write messages). If this doesn't work for you, Mauricio's may be a better bet.
using System;
using System.Diagnostics;
using System.Collections.Generic;
namespace FlimFlan.Diagnostics
{
public class ColorConsoleTraceListener : ConsoleTraceListener
{
Dictionary<TraceEventType, ConsoleColor> eventColor = new Dictionary<TraceEventType, ConsoleColor>();
public ColorConsoleTraceListener()
{
eventColor.Add(TraceEventType.Verbose, ConsoleColor.DarkGray);
eventColor.Add(TraceEventType.Information, ConsoleColor.Gray);
eventColor.Add(TraceEventType.Warning, ConsoleColor.Yellow);
eventColor.Add(TraceEventType.Error, ConsoleColor.DarkRed);
eventColor.Add(TraceEventType.Critical, ConsoleColor.Red);
eventColor.Add(TraceEventType.Start, ConsoleColor.DarkCyan);
eventColor.Add(TraceEventType.Stop, ConsoleColor.DarkCyan);
}
public override void TraceEvent(TraceEventCache eventCache, string source, TraceEventType eventType, int id, string message)
{
TraceEvent(eventCache, source, eventType, id, "{0}", message);
}
public override void TraceEvent(TraceEventCache eventCache, string source, TraceEventType eventType, int id, string format, params object[] args)
{
ConsoleColor originalColor = Console.ForegroundColor;
Console.ForegroundColor = getEventColor(eventType, originalColor);
base.TraceEvent(eventCache, source, eventType, id, format, args);
Console.ForegroundColor = originalColor;
}
private ConsoleColor getEventColor(TraceEventType eventType, ConsoleColor defaultColor)
{
if (!eventColor.ContainsKey(eventType))
{
return defaultColor;
}
return eventColor[eventType];
}
}
}
You can see it in action using the following app:
using System.Diagnostics;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
TraceSource trace = new TraceSource("log");
trace.TraceEvent(TraceEventType.Start, 0);
trace.TraceInformation("Hello World");
trace.TraceEvent(TraceEventType.Error, 0, "Something failed.");
trace.TraceEvent(TraceEventType.Verbose, 0, "I like ice cream.");
trace.TraceEvent(TraceEventType.Critical, 0, "Something went horribly wrong!");
trace.TraceEvent(TraceEventType.Verbose, 0, "I like cherries.");
trace.TraceEvent(TraceEventType.Warning, 0, "This program will end soon...");
trace.TraceEvent(TraceEventType.Information, 0, "Ending program.");
trace.TraceEvent(TraceEventType.Stop, 0);
}
}
}
Add these settings to the configuration section of your app.config:
<system.diagnostics>
<sources>
<source name="log" switchValue="All">
<listeners>
<add name="Console" type="FlimFlan.Diagnostics.ColorConsoleTraceListener, ConsoleApplication1" />
</listeners>
</source>
</sources>
</system.diagnostics>
And you should see something like this:
