No but world is Null. I changed my cod, but World always Null, and i dont know why it so, and how true get World.
void UMyBlueprintFunctionLibrary::Spawn(class UClass* clas )
{
FActorSpawnParameters param;
FVector loc = FVector(0, 0, 0);
FRotator rot = FRotator(0, 0, 0);
if (clas==NULL)
GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, "clas - false");
UWorld* const World = clas->GetWorld();
if (World)
World->SpawnActor(clas,&loc,&rot,param);
else
GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red,"World - false");
}