Application Developer Supplied User Function

Quick Question In Refernece To This Pool. In The Example provided the Application Developer Supploed User Function is decleared using the static keyword

static public void IOCPThreadFunction(Int32 iValue)

Is that necessary? The reason I ask is that the function I built is inside of a class. It needs to have access so some data within that class. I could write it otherwise but that would add a whole lot of extra layers.