[SOLVED] JSON Serializing and Deserializing C++

[CHADALAK1]

Hello Community!

I’ve been out of the loop with serializing and deserializing Json in C++. I know in C#, say example I have this

{
    "Name" : "Dude",
    "Age" : 12,
    "Occupation" : "duder"

}

And for the serialized class class

[Serializable]
public class Person
{
    public string Name;
    public int Age;
    public string Occupation;
}

I see everywhere online on how to retrieve the JSON text into a FJsonObject and FJsonReader, but I’m unsure on the steps to deserialize

C# (Unity) example

 string jsonString = /* DO FILE IO STUFF TO GET JSON file as string */
Person person = JsonUtility.FromJson<Person>(jsonString);  

How would one be able to deserialize a Person class from JSON in UE4 C++? Am I able to deserialize the values in a class/struct like this?

[Zeblote]

There is a tool to automatically serialize UStructs:

USTRUCT()
struct FPerson
{
    GENERATED_BODY()

public:
    UPROPERTY()
    FString Name;

    UPROPERTY()
    FString Occupation;

    UPROPERTY()
    int32 Age;
};

To read:

FString Blah = ...;
FPerson Person;

if(!FJsonObjectConverter::JsonObjectStringToUStruct(Blah, &Person, 0, 0))
{
    // error
}

To write:

FString Blah;
FPerson Person;

FJsonObjectConverter::UStructToJsonObjectString(Person, Blah);

[CHADALAK1]

@Zeblote

There is a tool to automatically serialize UStructs:

USTRUCT()
struct FPerson
{
GENERATED_BODY()

public:
UPROPERTY()
FString Name;

UPROPERTY()
FString Occupation;

UPROPERTY()
int32 Age;
};

To read:

FString Blah = ...;
FPerson Person;

if(!FJsonObjectConverter::JsonObjectStringToUStruct(Blah, &Person, 0, 0))
{
// error
}

To write:

FString Blah;
FPerson Person;

FJsonObjectConverter::UStructToJsonObjectString(Person, Blah);

Thank you soo much! Been looking around for this for quite some time. Muchly appreciate this!

[CHADALAK1]

    FString FilePath = "C:\\Users\\<YOUR_USER>\\Desktop\\Person.json";
    FString FileData = "";
    if (!FPlatformFileManager::Get().GetPlatformFile().FileExists(*FilePath))
    {
        UE_LOG(LogTemp, Warning, TEXT("DID NOT FIND FILE"));
        return;
    }

    FPerson PersonJSON;
    FFileHelper::LoadFileToString(FileData, *FilePath);

    UE_LOG(LogTemp, Warning, TEXT("%s"), *FileData);

    if (FJsonObjectConverter::JsonObjectStringToUStruct(FileData, &PersonJSON, 0, 0))
    {
        UE_LOG(LogTemp, Warning, TEXT("CONVERTED"));
        UE_LOG(LogTemp, Warning, TEXT("Name: %s Age: %d Occupation: %s"), *PersonJSON.Name, 
            PersonJSON.Age, *PersonJSON.Occupation);
    }

Just for persons needing a reference, this works out very well ^_^! able to get everything correct :D! Thank you again @**Zeblote !!! **

[SharpC1]

it works only for “Person” class, how can we use generic deserializing in c++?