AddComponentsToLevelActor

动态给Level中的Actor添加组件

参考源码：\Engine\Source\Editor\SubobjectDataInterface\Public\SubobjectDataSubsystem.h

SubobjectDataSubsystem 提供大量对Level中Actor的操作函数：

	/**
	* Gather all subobjects that the given UObject context has. Populates an array of 
	* handles that will have the given context and all it's subobjects.
	* 
	* @param Context		Object to gather subobjects for
	* @param OutArray		Array to populate (will be emptied first)
	*/
	void GatherSubobjectData(UObject* Context, TArray<FSubobjectDataHandle>& OutArray);

	////////////////////////////////////////////
	// System events
	
	/** Delegate invoked when a new subobject is successfully added */
	FOnNewSubobjectAdded& OnNewSubobjectAdded() { return OnNewSubobjectAdded_Delegate; };

	////////////////////////////////////////////

	/**
	* Gather all subobjects that the given Blueprint context has. Populates an array of
	* handles that will have the given context and all it's subobjects.
	*
	* @param Context		Object to gather subobjects for
	* @param OutArray		Array to populate (will be emptied first)
	*/
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem", meta = (DisplayName = "Gather Subobject Data For Blueprint"))
	void K2_GatherSubobjectDataForBlueprint(UBlueprint* Context, TArray<FSubobjectDataHandle>& OutArray);

	/**
	* Gather all subobjects that the given actor instance has. Populates an array of
	* handles that will have the given context and all it's subobjects.
	*
	* @param Context		Object to gather subobjects for
	* @param OutArray		Array to populate (will be emptied first)
	*/
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem", meta = (DisplayName = "Gather Subobject Data For Instance"))
	void K2_GatherSubobjectDataForInstance(AActor* Context, TArray<FSubobjectDataHandle>& OutArray);

	/**
	* Attempt to find the subobject data for a given handle. OutData will only 
	* be valid if the function returns true.
	*
	* @param Handle		Handle of the subobject data you want to acquire
	* @param OutData	Reference to the subobject data to populate
	*
	* @return bool		true if the data was found
	*/
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem", meta = (DisplayName = "FindSubobjectDataFromHandle"))
	bool K2_FindSubobjectDataFromHandle(const FSubobjectDataHandle& Handle, FSubobjectData& OutData) const;

	/**
	* Attempt to find an existing handle for the given object. 
	*
	* @param Context		The context that the object to find is within
	* @param ObjectToFind	The object that you want to find the handle for within the context
	*
	* @return FSubobjectDataHandle	The subobject handle for the object, Invalid handle if not found.
	*/
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem")
	FSubobjectDataHandle FindHandleForObject(const FSubobjectDataHandle& Context, const UObject* ObjectToFind, UBlueprint* BPContext = nullptr) const;
	
	////////////////////////////////////////////
	// Modifying subobjects

	/**
	 * Creates a new C++ component from the specified class type
	 * The user will be prompted to pick a new subclass name and code will be recompiled
	 *
	 * @return The new class that was created
	 */
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem", meta = (DisplayName = "Create New C++ Component"))
	static UClass* CreateNewCPPComponent(TSubclassOf<UActorComponent> ComponentClass, const FString& NewClassPath, const FString& NewClassName);

	/**
	 * Creates a new Blueprint component from the specified class type
	 * The user will be prompted to pick a new subclass name and a blueprint asset will be created
	 *
	 * @return The new class that was created
	 */
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem", meta = (DisplayName = "Create New Blueprint Component"))
	static UClass* CreateNewBPComponent(TSubclassOf<UActorComponent> ComponentClass, const FString& NewClassPath, const FString& NewClassName);
	
	/**
	* Add a new subobject as a child to the given parent object 
	*
	* @param Params			Options to consider when adding this subobject
	*
	* @return FSubobjectDataHandle		Handle to the newly created subobject, Invalid handle if creation failed
	*/
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem")
	FSubobjectDataHandle AddNewSubobject(const FAddNewSubobjectParams& Params, FText& FailReason);

	/**
	* Attempts to delete the given array of subobjects from their context 
	*
	* @param ContextHandle			The owning context of the subobjects that should be removed
	* @param SubobjectsToDelete		Array of subobject handles that should be deleted
	* @param BPContext				The blueprint context for the given
	* 
	* @return 	The number of subobjects successfully deleted
	*/
	UFUNCTION(BlueprintCallable, Category = "SubobjectDataSubsystem", meta = (DisplayName = "Delete Subobjects from Blueprint"))
	int32 DeleteSubobjects(const FSubobjectDataHandle& ContextHandle, const TArray<FSubobjectDataHandle>& SubobjectsToDelete, UBlueprint* BPContext = nullptr);

	/**