Load level from .pak file in Unreal 4.72

Development Programming & Scripting
1

Hi, how to load a level that is in .pak file?

I spend many hours researching and trying. There are many forum questions about this.

On recurring method I found is by using:

	if (FCoreDelegates::MountPak.IsBound())
	{
		FString pakPath = TEXT("../../../MyProject/Content/somePack.pak");
		IPakFile* pakFile = FCoreDelegates::MountPak.Execute(pakPath, 4);
		if (pakFile)
		{
			const auto& mountPoint = pakFile->PakGetMountPoint();
			UE_LOG(LogTemp, Warning, TEXT("LoadPakDelegate(): MountPoint %s"), *mountPoint);
			FString pakContentPath = mountPoint + "MyProject1/Content/";
			FPackageName::RegisterMountPoint("/Game/", pakContentPath);
			UGameplayStatics::OpenLevel(world, FName(TEXT("Map2")));
		}
	}
	else
	{
		UE_LOG(LogTemp, Warning, TEXT("LoadPakDelegate(): OnMountPak.IsBound() Falied"));
	}

I could only find this in Chinese website, stating that FCoreDelegates::MountPak.IsBound() will always return false in editor. (Of course we need editor method as-well, for developing thigs)
I also found many mentions that “EXCLUDE_NONPAK_UE_EXTENSIONS has to be set to 0”, and custom built engine needs to be built with this flag. This did not work, as everyone also experienced.