1. Epic GamesDeveloper
  3. Json

Json

API > API/Runtime

   
Name Json
Type Runtime
Location /Engine/Source/Runtime/Json/
Module Build Rules Json.Build.cs

Classes

Name Remarks
FAllocatorImpl TODO: Can remove this and just use rapidjson::CrtAllocator once RapidJsonIncludes.h starts overriding RAPIDJSON_MALLOC, etc.
FJsonObject A Json Object is a structure holding an unordered set of name/value pairs.
FJsonPointer JSON Pointer defines a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document (from rfc6901).
FJsonSerializerReader Implements the abstract serializer interface hiding the underlying reader object
FJsonSerializerWriter Implements the abstract serializer interface hiding the underlying writer object
FJsonValue A Json Value is a structure that can be any of the Json Types.
FJsonValueArray A Json Array Value.
FJsonValueBoolean A Json Boolean Value.
FJsonValueNull A Json Null Value.
FJsonValueNumber  
FJsonValueObject A Json Object Value.
TJsonReader  
TJsonReaderFactory  
TJsonSerializer  
TJsonStringReader  
TJsonStringViewReader  
TJsonStringWriter  
TJsonValueNumberString A Json Number Value, stored internally as a string so as not to lose precision
TJsonValueString A Json String Value.
TJsonWriter Template for Json writers.
TJsonWriterFactory  

Structs

Name Remarks
FJsonDataBag Useful if you just want access to the underlying FJsonObject (for cases where the schema is loose or an outer system will do further de/serialization)
FJsonObjectArrayUpdater Utility to update an array of json objects from an array of elements (of arbitrary type).
FJsonSerializable Base class for a JSON serializable object
FJsonSerializerBase Base interface used to serialize to/from JSON. Hides the fact there are separate read/write classes
FJsonSerializerPolicy_JsonObject  
FParseError  
TCondensedJsonPrintPolicy Template for print policies that generate compressed output.
TJsonPrintPolicy Base template for Json print policies.
TPrettyJsonBag  
TPrettyJsonPrintPolicy Template for print policies that generate human readable output.

Typedefs

Name Type Remarks Include Path
CondensedSerializer FJsonSerializerWriter< TCHAR, TCondensedJsonPrintPolicy< TCHAR > >   Serialization/JsonSerializable.h
CondensedWriter TSharedRef< TJsonWriter< TCHAR, TCondensedJsonPrintPolicy< TCHAR > > >   Serialization/JsonSerializable.h
FAllocator Private::FAllocatorImpl   JsonUtils/RapidJsonUtils.h
FArray FValue::Array   JsonUtils/RapidJsonUtils.h
FConstArray FValue::ConstArray   JsonUtils/RapidJsonUtils.h
FConstObject FValue::ConstObject Types that use TCHAR (for reading) JsonUtils/RapidJsonUtils.h
FDocument rapidjson::GenericDocument< FEncoding, FAllocator >   JsonUtils/RapidJsonUtils.h
FEncoding rapidjson::UTF16< TCHAR > Types that use TCHAR (common) JsonUtils/RapidJsonUtils.h
FJsonSerializableArray TArray< FString > Array of data Serialization/JsonTypes.h
FJsonSerializableArrayFloat TArray< float >   Serialization/JsonTypes.h
FJsonSerializableArrayInt TArray< int32 >   Serialization/JsonTypes.h
FJsonSerializableKeySimpleValueVariantMap TMap< FString, JsonSimpleValueVariant > Helps keep key values unique Serialization/JsonTypes.h
FJsonSerializableKeyValueMap TMap< FString, FString > Maps a key to a value Serialization/JsonTypes.h
FJsonSerializableKeyValueMapArrayInt TMap< FString, FJsonSerializableArrayInt >   Serialization/JsonTypes.h
FJsonSerializableKeyValueMapFloat TMap< FString, float >   Serialization/JsonTypes.h
FJsonSerializableKeyValueMapInt TMap< FString, int32 >   Serialization/JsonTypes.h
FJsonSerializableKeyValueMapInt64 TMap< FString, int64 >   Serialization/JsonTypes.h
FJsonSerializer TJsonSerializer< FJsonSerializerPolicy_JsonObject >   Serialization/JsonSerializer.h
FJsonStringReader TJsonStringReader< TCHAR >   Serialization/JsonReader.h
FJsonValueNumberString TJsonValueNumberString< TCHAR >   Dom/JsonValue.h
FJsonValueString TJsonValueString< TCHAR >   Dom/JsonValue.h
FMember FValue::Member   JsonUtils/RapidJsonUtils.h
FObject FValue::Object Types that use TCHAR (for writing) JsonUtils/RapidJsonUtils.h
FPrettyStringWriter rapidjson::PrettyWriter< FStringBuffer, FEncoding, FEncoding, FAllocator >   JsonUtils/RapidJsonUtils.h
FStringBuffer rapidjson::GenericStringBuffer< FEncoding, FAllocator >   JsonUtils/RapidJsonUtils.h
FStringRef FDocument::StringRefType   JsonUtils/RapidJsonUtils.h
FStringWriter rapidjson::Writer< FStringBuffer, FEncoding, FEncoding, FAllocator >   JsonUtils/RapidJsonUtils.h
FValue FDocument::ValueType   JsonUtils/RapidJsonUtils.h
JsonNumberValueVariants TVariant< int32, uint32, int64, float, double > We always read with the highest precisions (int64 or double), but we can write with any level of precision Serialization/JsonTypes.h
JsonSimpleValueVariant TVariant< bool, JsonNumberValueVariants, FString >   Serialization/JsonTypes.h
PrettySerializer FJsonSerializerWriter<>   Serialization/JsonSerializable.h
PrettyWriter TSharedRef< TJsonWriter<> >   Serialization/JsonSerializable.h
ReturnStringArgs TTuple< FString *, bool >   Serialization/JsonSerializable.h
ToJsonVariantArgs TVariant< ReturnStringArgs, WriterVariants >   Serialization/JsonSerializable.h
WriterVariants TVariant< PrettyWriter, CondensedWriter >   Serialization/JsonSerializable.h

Enums

Public

Name Remarks
EJson Json (JavaScript Object Notation) is a lightweight data-interchange format.
EJsonNotation  
EJsonToken  

Constants

Name Type Remarks Include Path
TokenToNotationTable EJsonNotation   Serialization/JsonReader.h

Functions

Public

Name Remarks Include Path Unreal Specifiers

StringType & AppendEscapeJsonString ( StringType& AppendTo,
const FString& StringVal
)

 Takes an input string and escapes it so it can be written as a valid Json string. Serialization/JsonWriter.h  

bool EJsonToken_IsShortValue ( EJsonToken Token
)

   Serialization/JsonTypes.h  

FString EscapeJsonString ( const FString& StringVal
)

 Takes an input string and escapes it so it can be written as a valid Json string. Serialization/JsonWriter.h  

bool HasDestinationJsonStringCharRepresentation ( SrcChar Char
)

 Takes an input source char representing and returns if it is possible to represent in DstChar expected encoding Serialization/JsonWriter.h  

bool operator!= ( const JsonNumberValueVariants& Lhs,
const FString& Rhs
)

   Dom/JsonValue.h  

bool operator!= ( const FString& Lhs,
const JsonNumberValueVariants& Rhs
)

   Dom/JsonValue.h  

bool operator!= ( const JsonNumberValueVariants& Lhs,
const JsonNumberValueVariants& Rhs
)

   Dom/JsonValue.h  

bool operator!= ( const JsonSimpleValueVariant& Lhs,
const JsonSimpleValueVariant& Rhs
)

   Dom/JsonValue.h  

bool operator== ( const JsonSimpleValueVariant& Lhs,
const JsonSimpleValueVariant& Rhs
)

 Global operators Dom/JsonValue.h  

bool operator== ( const JsonNumberValueVariants& Lhs,
const JsonNumberValueVariants& Rhs
)

   Dom/JsonValue.h  

bool operator== ( const JsonNumberValueVariants& Lhs,
const FString& Rhs
)

   Dom/JsonValue.h  

bool operator== ( const FString& Lhs,
const JsonNumberValueVariants& Rhs
)

   Dom/JsonValue.h  

FString ToString ( const JsonNumberValueVariants& InNumberVariant
)

   Dom/JsonValue.h  

TOptional< TEnum > UE::Json::GetEnumField ( FConstObject Object,
const TCHAR* FieldName
)

 Attempts to parse an enum from a string with a specified name JsonUtils/RapidJsonUtils.h  

FStringRef UE::Json::MakeStringRef ( FStringView Str
)

 Make a RapidJSON reference to the given string. JsonUtils/RapidJsonUtils.h  

FValue UE::Json::MakeStringValue ( FStringView Str,
FAllocator& Allocator
)

 Make a RapidJSON value that has a copy of the given string. JsonUtils/RapidJsonUtils.h  

JsonSimpleValueVariant UE::Json::ToSimpleJsonVariant ( const T& InSimpleValue
)

   Dom/JsonValue.h  

bool UE::JsonArray::Private::FromJson ( TArray< T >& OutArray,
TStringView< CharType > JsonString
)

   Serialization/JsonSerializable.h  

void UE::JsonArray::Private::ToJson ( TArray< T >& InArray,
const ToJsonVariantArgs& InArgs
)

   Serialization/JsonSerializable.h  

void UE::JsonArray::Private::ToJson_SerializeArrayElements ( TArray< T >& InArray,
SerializerArgsT... Args
)

   Serialization/JsonSerializable.h  

void UE::JsonArray::Private::ToJson_SerializeArrayElements ( TArray< T* >& InArray,
SerializerArgsT... Args
)

   Serialization/JsonSerializable.h  

Static

Name Remarks Include Path Unreal Specifiers

static bool UE::JsonArray::FromJson ( TArray< T >& OutArray,
const FString& JsonString
)

   Serialization/JsonSerializable.h  

static bool UE::JsonArray::FromJson ( TArray< T >& OutArray,
FString&& JsonString
)

   Serialization/JsonSerializable.h  

static bool UE::JsonArray::FromJson ( TArray< T >& OutArray,
FUtf8StringView JsonStringView
)

   Serialization/JsonSerializable.h  

static bool UE::JsonArray::FromJson ( TArray< T >& OutArray,
FWideStringView JsonStringView
)

   Serialization/JsonSerializable.h  

static const FString UE::JsonArray::ToJson ( TArray< T >& InArray,
const bool bPrettyPrint
)

 Non-const due to T::Serialize being a non-const function Serialization/JsonSerializable.h  

static void UE::JsonArray::ToJson ( TArray< T >& InArray,
Private::PrettyWriter& JsonWriter
)

   Serialization/JsonSerializable.h  

static void UE::JsonArray::ToJson ( TArray< T >& InArray,
Private::CondensedWriter& JsonWriter
)

   Serialization/JsonSerializable.h  

Ask questions and help your peers Developer Forums

Write your own tutorials or read those from others Learning Library

On this page