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  3. FArchive

FArchive

Base class for archives that can be used for loading, saving, and garbage collecting in a byte order neutral way.

API > API/Runtime > API/Runtime/Core > API/Runtime/Core/Serialization

Inheritance Hierarchy

References

   
Module Core
Header /Engine/Source/Runtime/Core/Public/Serialization/Archive.h
Include #include "Serialization/Archive.h"

Syntax

class FArchive : private FArchiveState

Remarks

Base class for archives that can be used for loading, saving, and garbage collecting in a byte order neutral way.

Variables

  Type Name Description
Public variable uint8: 1 ArAllowLazyLoading Whether to allow lazy loading of bulk/secondary data.
Public variable uint8: 1 ArContainsCode Quickly tell if an archive contains script code.
Public variable uint8: 1 ArContainsMap Used to determine whether FArchive contains a level or world.
Public variable const FCustomPropertyListNode * ArCustomPropertyList Custom property list attribute.
Public variable uint32 ArDebugSerializationFlags Custom serialization modifier flags can be used for anything
Public variable uint8: 1 ArForceByteSwapping Whether we should forcefully swap bytes.
Public variable uint8: 1 ArIgnoreArchetypeRef If true, we will not serialize archetype references for structs and classes.
Public variable uint8: 1 ArIgnoreClassGeneratedByRef If true, we will not serialize ClassGeneratedBy reference in UClass.
Public variable uint8: 1 ArIgnoreClassRef If true, UObject::Serialize will skip serialization of the Class property.
Public variable uint8: 1 ArIgnoreOuterRef If true, we will not serialize the Outer reference in UObject.
Public variable uint8: 1 ArIsCountingMemory Whether this archive is counting memory.
Public variable uint8: 1 ArIsFilterEditorOnly Whether editor only properties are being filtered from the archive (or has been filtered).
Public variable uint8: 1 ArIsModifyingWeakAndStrongReferences Whether a reference collector is modifying the references and wants both weak and strong ones
Public variable uint8: 1 ArIsNetArchive Whether or not this archive is sending/receiving network data
Public variable uint8: 1 ArIsObjectReferenceCollector Whether this archive only cares about serializing object references.
Public variable uint8: 1 ArIsSaveGame Whether this archive is saving/loading game state
Public variable int64 ArMaxSerializeSize Max size of data that this archive is allowed to serialize.
Public variable uint8: 1 ArMergeOverrides Set to false if OverriddenProperties should be cleared at the beginning of SerializeVersionedTaggedProperties.
Public variable uint8: 1 ArNoDelta If true, do not perform delta serialization of properties.
Public variable uint8: 1 ArNoIntraPropertyDelta If true, do not perform delta serialization within properties (e.g. TMaps and TSets).
Public variable uint32 ArPortFlags Modifier flags that be used when serializing UProperties
Public variable uint8: 1 ArRequiresLocalizationGather Used to determine whether FArchive contains data required to be gathered for localization.
Public variable int32 ArSerializingDefaults Whether we are currently serializing defaults. > 0 means yes, <= 0 means no.
Public variable uint8: 1 ArShouldSkipBulkData Whether bulk data serialization should be skipped or not.
Public variable uint8: 1 ArUseCustomPropertyList Set TRUE to use the custom property list attribute for serialization.

Constructors

  Type Name Description
Public function    
Public function  

FArchive ( const FArchive&
)

  

Destructors

  Type Name Description
Public function Virtual    

Functions

  Type Name Description
Public function Virtual void

AttachBulkData ( UObject* Owner,
FBulkData* BulkData
)

 Attaches/ associates the passed in bulk data object with the linker.
Public function Virtual void

AttachBulkData ( UE::Serialization::FEditorBulkData* BulkData
)

  
Public function Virtual bool Adds external read dependency
Public function FArchive &

ByteOrderSerialize ( void* V,
int32 Length
)

 Serialize data of Length bytes, taking into account byte swapping if needed.
Public function void

ByteSwap ( void* V,
int32 Length
)

 Used to do byte swapping on small items. This does not happen usually, so we don't want it inline.
Public function void Sets ArIsError to false, this does not clear any CriticalErrors
Public function Virtual bool

Close ()

 Attempts to close and finalize any handles used for backing data storage, returns true if it succeeded.
Public function Const bool Returns true if this archive contains native or generated code.
Public function Const bool Returns true if this archive contains a ULevel or UWorld object.
Public function Const const ITargetPlatform * Returns the cooking target platform.
Public function Const int32

CustomVer ( const FGuid& Key
)

 Queries a custom version from the archive.
Public function Virtual void

DetachBulkData ( UE::Serialization::FEditorBulkData* BulkData,
bool bEnsureBulkDataIsLoaded
)

  
Public function Virtual void

DetachBulkData ( FBulkData* BulkData,
bool bEnsureBulkDataIsLoaded
)

 Detaches the passed in bulk data object from the linker.
Public function Const bool

DoDelta ()

 Returns true if this archive should handle delta serialization for properties.
Public function Const bool Returns true if this archive should perform delta serialization within properties (e.g. TMaps and TSets).
Public function Const FEngineVersionBase Returns the compiled engine version used for this archive.
Public function bool

FastPathLoad ( void* InDest
)

  
Public function Virtual void

Flush ()

 Attempts to finish writing any buffered data to disk/permanent storage.
Public function Virtual void Flushes cache and frees internal data.
Public function Virtual void Inform the archive that a blueprint would like to force finalization, normally this is triggered by CDO load, but if there's no CDO we force finalization.
Public function Const bool Returns true if this archive should always swap bytes, ignoring endian rules.
Public function Const const FArchiveState &  
Public function FArchiveState & Returns the low level archive state for this archive.
Public function Virtual FArchive * Returns a pointer to an archive that represents the same data that the current archive covers, but that can be cached and reused later In the case of standard archives, this function will just return a pointer to itself.
Public function FArchiveCookContext *  
Public function FArchiveCookData *  
Public function Const uint32 Returns the editor-only debug serialization flags.
Public function Const bool  
Public function Const int64 Returns the maximum size of data that this archive is allowed to serialize.
Public function Const uint32 Returns this archive's property serialization modifier flags.
Public function FArchiveSavePackageData *  
Public function Const FProperty * Gets the property that is currently being serialized
Public function Const void

GetSerializedPropertyChain ( TArray< class FProperty* >& OutProperties
)

 Gets the chain of properties that are currently being serialized
Public function Const const FArchiveSerializedPropertyChain * Get the raw serialized property chain for this archive
Public function Const bool Checks to see if all of the passed in property serialization modifier flags are set.
Public function Const bool Checks to see if any of the passed in property serialization modifier flags are set.
Public function Const bool Returns true if this archive sould allow lazy loading of bulk / secondary data.
Public function bool Returns true if data larger than 1 byte should be swapped to deal with endian mismatches.
Public function Const bool Checks whether the archive is used for cooking.
Public function Const bool Returns true if this archive is counting memory, normally CountBytes is called to get the size.
Public function Const bool Returns true if this archive contains critical errors that cannot be recovered from.
Public function Const bool

IsError ()

 Returns true if this archive contains errors, which means that further serialization is generally not safe.
Public function Const bool Indicates whether this archive is filtering editor-only on save or contains data that had editor-only content stripped.
Public function Const bool Returns true if this archive wants to always save strings in UTF16 format even if they are ANSI characters.
Public function Const bool Returns true if this archive should ignore archetype references for structs and classes.
Public function Const bool Returns true if this archive should ignore the ClassGeneratedBy reference in UClass.
Public function Const bool Returns true if this archive should ignore the Class reference in UObject.
Public function Const bool Returns true if this archive should ignore the Outer reference in UObject.
Public function Const bool Returns true if this archive is for loading data.
Public function Const bool Returns true if this archive is loading from a cooked package.
Public function Const bool Returns true if this archive should modify/search weak object references as well as strong ones.
Public function Const bool Whether or not this archive is serializing data being sent/received by the netcode
Public function Const bool Returns true if this archive is only looking for UObject references.
Public function Const bool Returns true if this archive is saving or loading data destined for persistent storage and should skip transient data.
Public function Virtual Const bool

IsProxyOf ( FArchive* InOther
)

 Determine if the given archive is a valid "child" of this archive.
Public function Const bool Indicates whether this archive is saving or loading game state
Public function Const bool Returns true if this archive is for saving data, this can also be a pre-save preparation archive.
Public function Const bool Returns true if this archive is currently serializing class/struct default values.
Public function Const bool Returns true if this archive serializes to a structured text format.
Public function Const bool Returns true if this archive is transacting, which is used to keep track of changes to objects for things like the editor undo system.
Public function Const int32 Returns the licensee-specific version used for this archive, will be 0 by default.
Protected function Static void  
Public function void

Logf ( const FmtType& Fmt,
Types... Args
)

 Logf implementation for convenience.
Public function Virtual void

MarkScriptSerializationEnd ( const UObject* Obj
)

 Called when an object stops serializing property data using script serialization.
Public function Virtual void

MarkScriptSerializationStart ( const UObject* Obj
)

 Called when an object begins serializing property data using script serialization.
Public function Virtual Const void

MarkSearchableName ( const TObjectPtr< const UObject >& TypeObject,
const FName& ValueName
)

 Called to register a reference to a specific name value, of type TypeObject (UEnum or UStruct normally).
Public function Virtual void  
Public function Virtual void  
Public function Virtual void

PopSerializedProperty ( FProperty* InProperty,
const bool bIsEditorOnlyProperty
)

 Pop a property that was previously being serialized off the property stack
Public function Virtual bool

Precache ( int64 PrecacheOffset,
int64 PrecacheSize
)

 Hint the archive that the region starting at passed in offset and spanning the passed in size is going to be read soon and should be precached.
Public function Virtual void

Preload ( UObject* Object
)

 Tells the archive to attempt to preload the specified object so data can be loaded out of it.
Public function Virtual void

PushDebugDataString ( const FName& DebugData
)

 Debug stack storage if you want to add data to the archive for usage further down the serialization stack this should be used in conjunction with the FScopeAddDebugData struct
Public function Virtual void Called whilst cooking to provide file region hints to the cooker.
Public function Virtual void

PushSerializedProperty ( FProperty* InProperty,
const bool bIsEditorOnlyProperty
)

 Push a property that is currently being serialized onto the property stack
Public function Const bool Returns true if this archive contains data required to be gathered for localization.
Public function Virtual void

Seek ( int64 InPos
)

 Attempts to set the current offset into backing data storage, this will do nothing if there is no storage.
Public function Virtual void

Serialize ( void* V,
int64 Length
)

  
Public function Virtual void

SerializeBits ( void* V,
int64 LengthBits
)

  
Protected function Virtual void

SerializeBool ( bool& D
)

 Serializes a Boolean value from or into an archive.
Public function Virtual bool

SerializeBulkData ( FBulkData& BulkData,
const FBulkDataSerializationParams& Params
)

 Serialize bulk data.
Public function void

SerializeCompressed ( void* V,
int64 Length,
FName CompressionFormatCannotChange,
ECompressionFlags Flags,
bool bTreatBufferAsFileReader
)

 Serializes and compresses/ uncompresses data.
Public function void

SerializeCompressedNew ( void* V,
int64 Length,
FName CompressionFormatToEncode,
FName CompressionFormatToDecodeOldV1Files,
ECompressionFlags Flags,
bool bTreatBufferAsFileReader,
int64* OutPartialReadLength
)

 Serializes and compresses/ uncompresses data.
Public function void

SerializeCompressedNew ( void* V,
int64 Length
)

 Serializes and compresses/ uncompresses data with default compressor choices.
Public function Virtual void

SerializeInt ( uint32& Value,
uint32 Max
)

  
Public function Virtual void Packs int value into bytes of 7 bits with 8th bit for 'more'
Public function Virtual void  
Public function void

SetArchiveState ( const FArchiveState& InState
)

 Modifies current archive state, can be used to override flags.
Public function void

SetByteSwapping ( bool Enabled
)

 Toggle byte order swapping.
Public function Virtual bool

SetCompressionMap ( TArray< struct FCompressedChunk >* CompressedChunks,
ECompressionFlags CompressionFlags
)

 Sets mapping from offsets/ sizes that are going to be used for seeking and serialization to what is actually stored on disk.
Public function void

SetCookData ( FArchiveCookData* InCookData
)

  
Public function void Sets the archiver IsCriticalError and IsError to true.
Public function void

SetCustomVersion ( const FGuid& Key,
int32 Version,
FName FriendlyName
)

 Sets a specific custom version
Public function void Sets the archives custom serialization modifier flags (nothing to do with PortFlags or Custom versions)
Public function void Sets ArIsError to true. Also sets error in the proxy archiver if one is wrapping this.
Public function void

SetPortFlags ( uint32 InPortFlags
)

 Sets the archive's property serialization modifier flags
Public function void Marks that this archive is one of the archives used by SavePackage, and provides access to data and functions used only during savepackage, such as the cook data bundle for information about the cook being conducted (if applicable) and writing build dependencies for assetregistry.
Protected function void

SetShouldSkipCompilingAssets ( bool Enabled
)

 Set whether or not it is allowed to skip serialization on assets still being compiled to avoid waiting unless strictly necessary.
Public function void

SetShouldSkipUpdateCustomVersion ( bool bShouldSkip
)

 If set true, UsingCurrentVersion will not query the version registry to get the latest version data for the key if the version key is already set in the local container.
Public function Const bool Returns true if this archive should ignore bulk data.
Public function Const bool Returns true if it is allowed to skip serialization on assets still being compiled to avoid waiting unless strictly necessary.
Public function Const bool Returns true if this Archive is does not update the custom version data for a given key if has already been set previously in the local custom versions container
Public function void Sets a flag indicating that this archive is currently serializing class/struct defaults.
Public function void Indicate that this archive is no longer serializing class/struct defaults.
Public function void Sets a flag indicating that this archive contains native or generated code.
Public function void Sets a flag indicating that this archive contains a ULevel or UWorld object.
Public function void Sets a flag indicating that this archive contains data required to be gathered for localization.
Public function Const FPackageFileVersion

UEVer ()

 Returns the global engine serialization version used for this archive.
Protected function Static void  
Public function Const bool Returns true if tagged property serialization should be replaced by faster unversioned serialization.
Public function Virtual void

UsingCustomVersion ( const FGuid& Guid
)

 Registers the custom version to the archive.
Public function Const bool Returns true if this archive wants properties to be serialized in binary form instead of safer but slower tagged form.

Overridden from FArchiveState

  Type Name Description
Public function Virtual bool

AtEnd ()

 Returns true if the current location within the backing data storage is at the end, always returns false if there is no storage.
Public function Virtual void

CountBytes ( SIZE_T InNum,
SIZE_T InMax
)

 Called to get the computed size from a size-detecting archive after it has finished serializing.
Public function Virtual Const uint32 Returns the engine-global network protocol version for this archive.
Public function Virtual Const uint32 Returns the game-specific network protocol version for this archive.
Public function Virtual UObject *

GetArchetypeFromLoader ( const UObject* Obj
)

 Called to retrieve the archetype from the event driven loader.
Public function Virtual Const FString Returns the name of the Archive.
Public function Virtual Const const FCustomVersionContainer & Gets the custom version numbers for this archive.
Public function Virtual FArchiveState & Returns lowest level archive state, proxy archives will override this.
Public function Virtual FLinker * If this archive is a FLinkerLoad or FLinkerSave, returns a pointer to the ULinker portion.
Public function Virtual Const FString Get the localization namespace that this archive should use when serializing text properties.
Public function Virtual FUObjectSerializeContext * Gets the current UObject serialization context for this archive.
Public function Virtual Const bool Returns true if the stack of currently serialized properties contains an editor-only property
Public function Virtual void

Reset ()

 Resets all of the base archive members.
Public function Virtual void Resets the custom version numbers for this archive.
Public function Virtual void

SetCustomVersions ( const FCustomVersionContainer& CustomVersionContainer
)

 Sets the custom version numbers for this archive.
Public function Virtual void

SetEngineNetVer ( const uint32 InEngineNetVer
)

 Sets the archive engine network version.
Public function Virtual void

SetEngineVer ( const FEngineVersionBase& InVer
)

 Sets the archive engine version.
Public function Virtual void

SetFilterEditorOnly ( bool InFilterEditorOnly
)

 Sets a flag indicating that this archive needs to filter editor-only content.
Public function Virtual void

SetForceUnicode ( bool bInForceUnicode
)

 Sets whether this archive wants to force saving as Unicode.
Public function Virtual void

SetGameNetVer ( const uint32 InGameNetVer
)

 Sets the archive game network version.
Public function Virtual void

SetIsLoading ( bool bInIsLoading
)

 Sets whether this archive is for loading data.
Public function Virtual void

SetIsLoadingFromCookedPackage ( bool bInIsLoadingFromCookedPackage
)

 Sets whether the archive is loading from a cooked package.
Public function Virtual void

SetIsPersistent ( bool bInIsPersistent
)

 Sets whether this archive is to persistent storage.
Public function Virtual void

SetIsSaving ( bool bInIsSaving
)

 Sets whether this archive is for saving data.
Public function Virtual void

SetIsTextFormat ( bool bInIsTextFormat
)

 Sets whether this archive is in text format.
Public function Virtual void

SetIsTransacting ( bool bInIsTransacting
)

 Sets whether this archive is for transacting.
Public function Virtual void Sets the archive licensee version number.
Public function Virtual void

SetLocalizationNamespace ( const FString& InLocalizationNamespace
)

 Set the localization namespace that this archive should use when serializing text properties.
Public function Virtual void

SetSerializeContext ( FUObjectSerializeContext* InLoadContext
)

 Sets the current UObject serialization context for this archive.
Public function Virtual void

SetSerializedProperty ( FProperty* InProperty
)

 Overrides the property that is currently being serialized
Public function Virtual void

SetSerializedPropertyChain ( const FArchiveSerializedPropertyChain* InSerializedPropertyChain,
FProperty* InSerializedPropertyOverride
)

 Set the raw serialized property chain for this archive, optionally overriding the serialized property too (or null to use the head of the property chain)
Public function Virtual void Sets the archive version number.
Public function Virtual void

SetUseUnversionedPropertySerialization ( bool bInUseUnversioned
)

 Sets whether tagged property serialization should be replaced by faster unversioned serialization.
Public function Virtual void

SetWantBinaryPropertySerialization ( bool bInWantBinaryPropertySerialization
)

 Sets whether this archive wants binary property serialization.
Public function Virtual Const bool

ShouldSkipProperty ( const FProperty* InProperty
)

 Checks whether the archive wants to skip the property independent of the other flags
Public function Virtual int64

Tell ()

 Returns the current location within the backing data storage, which can possibly be passed to Seek later to restore a read/write location.
Public function Virtual int64 Returns total size of the backing data storage.
Public function Virtual Const bool Checks whether the archive is used to resolve out-of-date enum indexes If function returns true, the archive should be called only for objects containing user defined enum

Operators

  Type Name Description
Public function Virtual FArchive &

operator<< ( FField*& Value
)

 Serializes a Field value from or into this archive.
Public function Virtual FArchive &

operator<< ( FName& Value
)

 Serializes an FName value from or into this archive.
Public function Virtual FArchive &

operator<< ( FText& Value
)

 Serializes an FText value from or into an archive.
Public function Virtual FArchive &

operator<< ( UObject*& Value
)

 Serializes an UObject value from or into this archive.
Public function FArchive &

operator<< ( TCheckedObjPtr< T >& Value
)

 Serializes a UObject wrapped in a TCheckedObjPtr container, using the above operator, and verifies the serialized object is derived from the correct base class, to prevent illegal casting.
Public function Virtual FArchive &

operator<< ( FWeakObjectPtr& Value
)

 Serializes FWeakObjectPtr value from or into this archive.
Public function Virtual FArchive &

operator<< ( FObjectPtr& Value
)

 Serializes a wrapped object pointer value from or into this archive.
Public function Virtual FArchive &

operator<< ( FSoftObjectPtr& Value
)

 Serializes asset pointer from or into this archive.
Public function Virtual FArchive &

operator<< ( FSoftObjectPath& Value
)

 Serializes soft object paths from or into this archive.
Public function Virtual FArchive &

operator<< ( FLazyObjectPtr& Value
)

 Serializes a lazy object pointer value from or into this archive.
Public function FArchive &

operator= ( const FArchive& ArchiveToCopy
)

  

Classes

  Type Name Description
Public class FScopeAddDebugData    
Public class FScopeSeekTo Seeks to and restores the position of an archive.  
Public class FScopeSetDebugSerializationFlags    

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