The following is the JSON file I am trying to parse:-
{
"GameSetting":{
"Num_Levels":"3",
"Env_Type":"Indoor"
},
"Indoor":[
{
"Name":"simple room",
"objects":[
{"objectName":"chair"},
{"objectName":"tables"},
{"objectName":"boxes"},
{"objectName":"barrels"}
],
"number_of_objects":"10"
},
{
"Name":"multistory",
"objects":[
{ "objectName":"chair"},
{"objectName":"tables"},
{"objectName":"railings"},
{"objectName":"staircase"}
],
"number_of_objects":"25"
},
{
"Name":"passageway",
"objects":[
{"objectName":"forklift"},
{"objectName":"tables"},
{"objectName":"rooms"},
{"objectName":"doors"}
],
"number_of_objects":"32"
}
],
"Outdoor":[
{
"Name":"Downtown",
"objects":[
{"objectName":"Tall buildings"},
{"objectName":"medium buildings"},
{"objectName":"cars"},
{"objectName":"people"}
],
"number_of_objects":"10",
"Weather":"sunny",
"Wind":"Yes"
},
{
"Name":"Neighborhood",
"objects":[
{"objectName":"houses"},
{"objectName":"complexes"},
{"objectName":"community area"},
{"objectName":"park"},
{"objectName":"cars"},
{"objectName":"people"}
],
"number_of_objects":"25",
"Weather":"rainy",
"Wind":"Yes"
},
{
"Name":"Forest",
"objects":[
{"objectName":"trees"},
{"objectName":"lake"},
{"objectName":"mountains"}
],
"number_of_objects":"32",
"Weather":"rainy",
"Wind":"No"
}
]
}
I am using the approach specified in the answer of this question: C++ Nested JSON in Unreal Engine 4 - Stack Overflow
I am successfully able to access GameSetting’s both properties, Indoor’s Name and number_of_objects properties and Outdoor’s Name, number_of_objects, Wind and Weather properties. The only property I am having trouble with is the object arrays in both Indoor and Outdoor.
The following is my header file:
#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "JsonParser.generated.h"
USTRUCT()
struct FGameSetting
{
GENERATED_USTRUCT_BODY()
UPROPERTY()
FString Num_Levels;
UPROPERTY()
FString Env_Type;
};
USTRUCT()
struct FArrayBasic
{
GENERATED_USTRUCT_BODY()
UPROPERTY()
FString objectName;
};
USTRUCT()
struct FIndoorBasic
{
GENERATED_USTRUCT_BODY()
UPROPERTY()
FString Name;
TArray <FArrayBasic> objects;
UPROPERTY()
FString number_of_objects;
};
USTRUCT()
struct FOutDoorBasic
{
GENERATED_USTRUCT_BODY()
UPROPERTY()
FString Name;
TArray <FArrayBasic> objects;
UPROPERTY()
FString number_of_objects;
UPROPERTY()
FString Weather;
UPROPERTY()
FString Wind;
};
USTRUCT()
struct FMain
{
GENERATED_USTRUCT_BODY()
UPROPERTY()
FGameSetting GameSetting;
UPROPERTY()
TArray<FIndoorBasic>Indoor;
UPROPERTY()
TArray<FOutDoorBasic>Outdoor;
};
UCLASS()
class JSONPARSING_API AJsonParser : public AActor
{
GENERATED_BODY()
public:
// Sets default values for this actor's properties
AJsonParser();
protected:
// Called when the game starts or when spawned
virtual void BeginPlay() override;
public:
// Called every frame
virtual void Tick(float DeltaTime) override;
};
and .cpp file:
// Fill out your copyright notice in the Description page of Project Settings.
#include "JsonParser.h"
#include "JsonUtilities.h"
// Sets default values
AJsonParser::AJsonParser()
{
// Set this actor to call Tick() every frame. You can turn this off to improve performance if you don't need it.
PrimaryActorTick.bCanEverTick = true;
}
// Called when the game starts or when spawned
void AJsonParser::BeginPlay()
{
Super::BeginPlay();
const FString JsonFilePath = FPaths::ProjectContentDir() + "/JsonFiles/randomgenerated.json";
FString JsonString; //Json converted to FString
FFileHelper::LoadFileToString(JsonString,*JsonFilePath);
//Displaying the json in a string format inside the output log
GLog->Log("Json String:");
GLog->Log(JsonString);
//Create a json object to store the information from the json string
//The json reader is used to deserialize the json object later on
TSharedPtr<FJsonObject> JsonObject = MakeShareable(new FJsonObject());
TSharedRef<TJsonReader<>> JsonReader = TJsonReaderFactory<>::Create(JsonString);
if (FJsonSerializer::Deserialize(JsonReader, JsonObject) && JsonObject.IsValid())
{
FMain Main;
FJsonObjectConverter::JsonObjectStringToUStruct<FMain>(JsonString, &Main, 0, 0);
FString Data = Main.Outdoor[0].Wind;
//FArrayBasic Data1 = Main.Indoor[0].objects.GetData[0];
GLog->Log("sfdjngejbfwjqwnoesfjkesngkwbegjkwefbnjk");
GLog->Log(Data);
//for (int32 index = 0; index<Data.Num(); index++)
//{
// GLog->Log("name:" + Data[index]->AsString());
//}
//The person "object" that is retrieved from the given json file
TSharedPtr<FJsonObject> GameSetting = JsonObject->GetObjectField("GameSetting");
//Getting various properties
GLog->Log("ENV_TYPE:" + GameSetting->GetStringField("ENV_TYPE"));
GLog->Log("NUM_LEVELS:" + FString::FromInt(GameSetting->GetIntegerField("NUM_LEVELS")));
//Retrieving an array property and printing each field
/*TArray<TSharedPtr<FJsonValue>> objArray=PersonObject->GetArrayField("family");
GLog->Log("printing family names...");
for(int32 index=0;index<objArray.Num();index++)
{
GLog->Log("name:"+objArray[index]->AsString());
}*/
}
else
{
GLog->Log("couldn't deserialize");
}
}
// Called every frame
void AJsonParser::Tick(float DeltaTime)
{
Super::Tick(DeltaTime);
}
It would be extremely helpful if anyone can help me parse the array within the array in the JSON file using the same methodology. Thanks in advance.