#ifdef and #ifndef have no affect in header files

#ifdef and #ifndef have no affect when used in the header file of a class.

Ex:

#ifndef MYMACRO
	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Test)
		float ANumber;
#endif

ANumber variable does not show up in the editor when MYMACRO is not defined. Inverse also does not appear in editor (using #ifdef with macro defined)

1. Open UE4 Editor
2. Add code to project based on Actor (MyActor)
3. In MyActor.h add the following:

   #ifndef RANDO
   	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = Test)
   		float ANumber;
   #endif
   

4. Compile
5. Create blueprint based on MyActor (MyActorBP)
6. Add instance of MyActorBP to the level

Result:
ANumber does not appear in the details panel for the MyActorBP instance

Expected:
Since

Why does the REMOVE method of map container remove elements have memory leaks?

How does TextureRenderTarget2D get TArray<uint8> type data?

How do I set a material as a post-processing material?

UMG RichText not appear image when packaged

Do I need to call Destory method to remove components from Actor when Destory method to remove Actor?

How to delete some elements correctly when deleting an array loop?

What is the difference between Camera and CineCamera?

In UE5.4, custom variables in the level blueprint cannot be set to default values, and the eyedropper tool is also unavailable, whereas in UE4.27, these features work normally.

What controls of umg have mouse wheel events in UE4.27?

How to implement springarm components to scale according to mouse position in spawn?