Using static properties as class wide data
This is one of those things that is so obvious I wonder why it never occured to me before! If you declare a member as static the compiler only creates one member instance across all class instances.
class ClassWideStatic { protected static int NoOfInstances; public ClassWideStatic() { //setting NoOfInstances here will set it on ALL instances //effectively resetting it, but modifying it is fine NoOfInstances += 1; } static ClassWideStatic() { //This is a special constructor that is only called when //the first instance is created NoOfInstances = 1; } }