What is the difference between GetClass() and StaticClass()?

Development Programming & Scripting
1

For example, if I want to spawn an actor one of input parameters is UClassclass.
I can assign what class to spawn two different ways, by ABomb BombClass->GetClass() and ABomb::StaticClass()
As I can tell, the first one creates instance, the other doesn’t, can somebody confirm me that?
And what about performance? Which should I use?

1 Like
2

Hi,

UType::StaticClass() returns the class for UType, whereas Obj->GetClass() returns the class for whichever type Obj was created as, even if you’re calling it through a base pointer.

For example:

AMyActor* ActorPtr = NewObject<AMyActor>(...);
UObject*  ObjPtr   = Actor;

UClass* MyActorClass  = AMyActor::StaticClass(); // AMyActor
UClass* ObjectClass   = UObject::StaticClass();  // UObject
UClass* ActorPtrClass = ActorPtr->GetClass();    // AMyActor
UClass* ObjPtrClass   = ObjPtr->GetClass();      // AMyActor

Hope this helps,

Steve

3 Likes
3

ahh I see, so UType::StaticClass() is definite, while Obj->GetClass() can be dynamic, since pointer can be reassigned to different object. Thanks man!

4

That’s how polymorphism and virtual functions work. Suppose we have following classes:

class A{
public:
    int fun(){return 1;}
};
class B : public A{ //B inherits from A
public:
    int fun(){return 2;} //hides A::fun method
};

int main(){
    A* a = new A; 
    A* b = new B;
    B* c = (B*)b;
    a->fun(); //returns 1
    b->fun(); //still returns 1
    c->fun(); //returns 2!
}

But when I add virtual before int fun() in class A body, b->fun() will return 2 instead of 1. Magic! :smiley:

5

yeah i got that, virtual can be overridden by their child class
anyways, thanks man, appreciate it. it can get messy starting with lots of info and not knowing what to implement