How would you refactor this smelly code? (Logging, Copy and Paste, .Net 3.5)

Question

I've got code like this:

Logger logger = new Logger();
System.Diagnostics.Stopwatch stopWatch = new System.Diagnostics.Stopwatch();
logger.LogInformation("Calling SomeObject.SomeMethod at " + DateTime.Now.ToString());
stopWatch.Start();
// This is the method I'm interested in.
SomeResponse response = someObject.SomeMethod(someParam);
stopWatch.Stop();
logger.LogInformation("SomeObject.SomeMethod returned at " + DateTime.Now.ToString());
logger.LogInformation("SomeObject.SomeMethod took " + stopWatch.ElapsedMilliseconds + " milliseconds.");

I need to wrap similar code around a lot more objects and their methods to do some performance profiling. I'm not allowed to use 3rd party plugins or software, etc.

I'd really rather not write this same code around all of these method calls this all of this logging code. How would you refactor this to eliminate some of my coding effort?

If I'm not being very clear, please ask questions in the comments and I will try to clarify.

Thanks for any help!!

Answer 1

You can refactor the code to accept a method pointer instance (aka System.Action).

public void CallWithLogTiming (Action theAction)
{
  Logger logger = new Logger();
  System.Diagnostics.Stopwatch stopWatch = new System.Diagnostics.Stopwatch();
  logger.LogInformation("Calling SomeObject.SomeMethod at " + DateTime.Now.ToString());
  stopWatch.Start();

// This is the method I'm interested in.
  theAction();

  stopWatch.Stop();
  logger.LogInformation("SomeObject.SomeMethod returned at " + DateTime.Now.ToString());
  logger.LogInformation("SomeObject.SomeMethod took " + stopWatch.ElapsedMilliseconds + " milliseconds.");
}

Then you can call it by creating a lambda expression. Since myResponse is a captured variable, it will be populated when this Action is run and myResponse will be available for use later in this scope.

SomeResponse myResponse = null;
CallWithLogTiming( () => myResponse = someObject.SomeMethod(someParam) );

Answer 2

For simplicity sake, you could use generics, like so (off the top of my head):

public T MyLogMethod<T,S>(Func<S, T> someFunction, S someParameter) {}

Func(S,T) where S is the parameter type of the method, and T is the return type.