由於繼承自UBlueprintFunctionLibrary的子類中宣告的函式基本上是static，

在類內部呼叫外部定義的委託編譯時會報錯，按如下方式進行操作則可正常使用。

*.h

 1 UCLASS()
 2 class UE4_OSS_LIBRARY_API UOSSApiUtilty : public UBlueprintFunctionLibrary
 3 {
 4 GENERATED_BODY()
 5 public:
 6 
 7 DECLARE_DYNAMIC_DELEGATE_TwoParams(FOssPutObjComplete, bool, IsSuccess, FString, Err);
 
 8 
 9 UFUNCTION(BlueprintCallable, Category = "OSS_Api")
10 static void SetOssPutObjComplete(FOssPutObjComplete OnOssPutObjComplete);
11 
12 static void OnOssPutObjComplete(bool IsSuccess, FString Err);
13 
14 };

*.cpp

 1 static UOSSApiUtilty::FOssPutObjComplete OssPutObjComplete;
 2 
 3 void UOSSApiUtilty::SetOssPutObjComplete(FOssPutObjComplete OnOssPutObjComplete)
 4 {
 5     OssPutObjComplete = OnOssPutObjComplete;
 6 }
 7 
 8 void UOSSApiUtilty::OnOssPutObjComplete(bool IsSuccess, FString Err)
 9 {
10     OssPutObjComplete.ExecuteIfBound(IsSuccess, Err);
11 }
 

在藍圖中呼叫函式