Hi,

I was going through the examples and saw this:
       // Log a debug message. Test if debug is enabled before
       // attempting to log the message. This is not required but
       // can make running without logging faster.
       if (log.IsDebugEnabled) log.Debug("This is a debug message");

My question is, why not just check this in LogImpl.Debug() , i.e.
       virtual public void Debug(object message)
       {
               if( this.IsDebugEnabled ) Logger.Log(ThisDeclaringType,
m_levelDebug, message, null);
}

And then of course do the same for DebugFormat, Info, Warn, etc. etc.
I haven't dug much into the code but I'm interested in using the
framework.  It just seems to me that if you really get a performance
enhancement from testing if IsDebugEnabled before calling it, it would
make more sense to save that step everywhere you make that Debug()
call in paractice.

I'm guessing there's a good reason why, but could someone tell me?

Thanks.
-Tom

Yes, the reason is that sometimes it takes a while to generate the argument
to log.Debug(). If your code looks something like:

    log.Debug(CallReallySlowComponentAndGenerateAMessage());

you would of course benefit from using

    if (log.IsDebugEnabled)
        log.Debug(CallReallySlowComponentAndGenerateAMessage());

instead, since the time-consuming generation of the message will not occur.
If you only log string literals, I suppose there is no point in using this
construct.

/Göran

Good morning Tom,

My understanding is that you should use IsXXXEnabled for situations
where "message" is computationally expensive to create.

--Chris

I use the boolean check do other things as well.

if(this.IsDebugEnabled){
        string message = ExpensiveMessaegCreation();
        Logger.Log(ThisDeclaringType, m_levelDebug, message, null);
}

dru

Okay, thanks for the clarification everyone.
How computationally expensive is something simple like:

Log.Debug( "Couldn't connect to: " + connectionString );

That's the majority of what my messages would look like.

Thanks!
-Tom