Can using lambdas as event handlers cause a memory leak?

Question

Say we have the following method:

private MyObject foo = new MyObject();

// and later in the class

public void PotentialMemoryLeaker(){
  int firedCount =          


        

Answer 1

Yes, save it to a variable and unhook it.

DelegateType evt = (o, e) => { firedCount++; Console.Write(firedCount); };
foo.AnEvent += evt;
foo.MethodThatFiresAnEvent();
foo.AnEvent -= evt;

And yes, if you don't, you'll leak memory, as you'll hook up a new delegate object each time. You'll also notice this because each time you call this method, it'll dump to the console an increasing number of lines (not just an increasing number, but for one call to MethodThatFiresAnEvent it'll dump any number of items, once for each hooked up anonymous method).