#include <v8.h>

Inheritance diagram for String:

[legend]

Collaboration diagram for String:

[legend]

Data Structures
class	ExternalOneByteStringResource

class	ExternalStringResource

class	ExternalStringResourceBase

class	Utf8Value

class	Value

Public Types
enum	Encoding { UNKNOWN_ENCODING = 0x1 , TWO_BYTE_ENCODING = 0x0 , ONE_BYTE_ENCODING = 0x8 }

enum	WriteOptions { NO_OPTIONS = 0 , HINT_MANY_WRITES_EXPECTED = 1 , NO_NULL_TERMINATION = 2 , PRESERVE_ONE_BYTE_NULL = 4 , REPLACE_INVALID_UTF8 = 8 }

Public Member Functions
int	Length () const

int	Utf8Length (Isolate *isolate) const

bool	IsOneByte () const

bool	ContainsOnlyOneByte () const

int	Write (Isolate isolate, uint16_t buffer, int start=0, int length=-1, int options=NO_OPTIONS) const

int	WriteOneByte (Isolate isolate, uint8_t buffer, int start=0, int length=-1, int options=NO_OPTIONS) const

int	WriteUtf8 (Isolate isolate, char buffer, int length=-1, int *nchars_ref=nullptr, int options=NO_OPTIONS) const

bool	IsExternal () const

bool	IsExternalTwoByte () const

bool	IsExternalOneByte () const

V8_INLINE ExternalStringResourceBase *	GetExternalStringResourceBase (Encoding *encoding_out) const

V8_INLINE ExternalStringResource *	GetExternalStringResource () const

const ExternalOneByteStringResource *	GetExternalOneByteStringResource () const

bool	MakeExternal (ExternalStringResource *resource)

bool	MakeExternal (ExternalOneByteStringResource *resource)

bool	CanMakeExternal () const

bool	StringEquals (Local< String > str) const

template<>
V8_WARN_UNUSED_RESULT Local< String >	NewFromUtf8Literal (Isolate *isolate, const char(&literal)[1], NewStringType type)

Public Member Functions inherited from Name
int	GetIdentityHash ()

Public Member Functions inherited from Value
V8_INLINE bool	IsUndefined () const

V8_INLINE bool	IsNull () const

V8_INLINE bool	IsNullOrUndefined () const

bool	IsTrue () const

bool	IsFalse () const

bool	IsName () const

V8_INLINE bool	IsString () const

bool	IsSymbol () const

bool	IsFunction () const

bool	IsArray () const

bool	IsObject () const

bool	IsBigInt () const

bool	IsBoolean () const

bool	IsNumber () const

bool	IsExternal () const

bool	IsInt32 () const

bool	IsUint32 () const

bool	IsDate () const

bool	IsArgumentsObject () const

bool	IsBigIntObject () const

bool	IsBooleanObject () const

bool	IsNumberObject () const

bool	IsStringObject () const

bool	IsSymbolObject () const

bool	IsNativeError () const

bool	IsRegExp () const

bool	IsAsyncFunction () const

bool	IsGeneratorFunction () const

bool	IsGeneratorObject () const

bool	IsPromise () const

bool	IsMap () const

bool	IsSet () const

bool	IsMapIterator () const

bool	IsSetIterator () const

bool	IsWeakMap () const

bool	IsWeakSet () const

bool	IsArrayBuffer () const

bool	IsArrayBufferView () const

bool	IsTypedArray () const

bool	IsUint8Array () const

bool	IsUint8ClampedArray () const

bool	IsInt8Array () const

bool	IsUint16Array () const

bool	IsInt16Array () const

bool	IsUint32Array () const

bool	IsInt32Array () const

bool	IsFloat32Array () const

bool	IsFloat64Array () const

bool	IsBigInt64Array () const

bool	IsBigUint64Array () const

bool	IsDataView () const

bool	IsSharedArrayBuffer () const

bool	IsProxy () const

bool	IsWasmMemoryObject () const

bool	IsWasmModuleObject () const

bool	IsModuleNamespaceObject () const

V8_WARN_UNUSED_RESULT MaybeLocal< BigInt >	ToBigInt (Local< Context > context) const

V8_WARN_UNUSED_RESULT MaybeLocal< Number >	ToNumber (Local< Context > context) const

V8_WARN_UNUSED_RESULT MaybeLocal< String >	ToString (Local< Context > context) const

V8_WARN_UNUSED_RESULT MaybeLocal< String >	ToDetailString (Local< Context > context) const

V8_WARN_UNUSED_RESULT MaybeLocal< Object >	ToObject (Local< Context > context) const

V8_WARN_UNUSED_RESULT MaybeLocal< Integer >	ToInteger (Local< Context > context) const

V8_WARN_UNUSED_RESULT MaybeLocal< Uint32 >	ToUint32 (Local< Context > context) const

V8_WARN_UNUSED_RESULT MaybeLocal< Int32 >	ToInt32 (Local< Context > context) const

Local< Boolean >	ToBoolean (Isolate *isolate) const

V8_WARN_UNUSED_RESULT MaybeLocal< Uint32 >	ToArrayIndex (Local< Context > context) const

bool	BooleanValue (Isolate *isolate) const

V8_WARN_UNUSED_RESULT Maybe< double >	NumberValue (Local< Context > context) const

V8_WARN_UNUSED_RESULT Maybe< int64_t >	IntegerValue (Local< Context > context) const

V8_WARN_UNUSED_RESULT Maybe< uint32_t >	Uint32Value (Local< Context > context) const

V8_WARN_UNUSED_RESULT Maybe< int32_t >	Int32Value (Local< Context > context) const

V8_WARN_UNUSED_RESULT Maybe< bool >	Equals (Local< Context > context, Local< Value > that) const

bool	StrictEquals (Local< Value > that) const

bool	SameValue (Local< Value > that) const

Local< String >	TypeOf (Isolate *)

Maybe< bool >	InstanceOf (Local< Context > context, Local< Object > object)

template<class T >
Value *	Cast (T *value)

template<>
V8_INLINE Value *	Cast (Data *value)

Public Member Functions inherited from Data
bool	IsValue () const

bool	IsModule () const

bool	IsPrivate () const

bool	IsObjectTemplate () const

bool	IsFunctionTemplate () const

bool	IsContext () const

Static Public Member Functions
static V8_INLINE Local< String >	Empty (Isolate *isolate)

static V8_INLINE String *	Cast (v8::Data *data)

template<int N>
static V8_WARN_UNUSED_RESULT Local< String >	NewFromUtf8Literal (Isolate *isolate, const char(&literal)[N], NewStringType type=NewStringType::kNormal)

static V8_WARN_UNUSED_RESULT MaybeLocal< String >	NewFromUtf8 (Isolate isolate, const char data, NewStringType type=NewStringType::kNormal, int length=-1)

static V8_WARN_UNUSED_RESULT MaybeLocal< String >	NewFromOneByte (Isolate isolate, const uint8_t data, NewStringType type=NewStringType::kNormal, int length=-1)

static V8_WARN_UNUSED_RESULT MaybeLocal< String >	NewFromTwoByte (Isolate isolate, const uint16_t data, NewStringType type=NewStringType::kNormal, int length=-1)

static Local< String >	Concat (Isolate *isolate, Local< String > left, Local< String > right)

static V8_WARN_UNUSED_RESULT MaybeLocal< String >	NewExternalTwoByte (Isolate isolate, ExternalStringResource resource)

static V8_WARN_UNUSED_RESULT MaybeLocal< String >	NewExternalOneByte (Isolate isolate, ExternalOneByteStringResource resource)

Static Public Member Functions inherited from Name
static V8_INLINE Name *	Cast (Data *data)

Static Public Member Functions inherited from Value
template<class T >
static V8_INLINE Value *	Cast (T *value)

Static Public Attributes
static constexpr int	kMaxLength

Detailed Description

A JavaScript string value (ECMA-262, 4.3.17).

Definition at line 3203 of file v8.h.

Member Enumeration Documentation

◆ Encoding

enum Encoding

Enumerator
UNKNOWN_ENCODING
TWO_BYTE_ENCODING
ONE_BYTE_ENCODING

Definition at line 3208 of file v8.h.

◆ WriteOptions

enum WriteOptions

Write the contents of the string to an external buffer. If no arguments are given, expects the buffer to be large enough to hold the entire string and NULL terminator. Copies the contents of the string and the NULL terminator into the buffer.

WriteUtf8 will not write partial UTF-8 sequences, preferring to stop before the end of the buffer.

Copies up to length characters into the output buffer. Only null-terminates if there is enough space in the buffer.

Parameters

buffer	The buffer into which the string will be copied.
start	The starting position within the string at which copying begins.
length	The number of characters to copy from the string. For WriteUtf8 the number of bytes in the buffer.
nchars_ref	The number of characters written, can be NULL.
options	Various options that might affect performance of this or subsequent operations.

Returns: The number of characters copied to the buffer excluding the null terminator. For WriteUtf8: The number of bytes copied to the buffer including the null terminator (if written).

Enumerator
NO_OPTIONS
HINT_MANY_WRITES_EXPECTED
NO_NULL_TERMINATION
PRESERVE_ONE_BYTE_NULL
REPLACE_INVALID_UTF8

Definition at line 3264 of file v8.h.

Member Function Documentation

◆ CanMakeExternal()

bool CanMakeExternal ( ) const

Returns true if this string can be made external.

◆ Cast()

String * Cast ( v8::Data * data )

static

Definition at line 11668 of file v8.h.

◆ Concat()

static Local<String> Concat	(	Isolate *	isolate,
		Local< String >	left,
		Local< String >	right
	)

static

Creates a new string by concatenating the left and the right strings passed in as parameters.

◆ ContainsOnlyOneByte()

bool ContainsOnlyOneByte ( ) const

Returns whether this string contain only one byte data, i.e. ISO-8859-1 code points. Will read the entire string in some cases.

◆ Empty()

Local< String > Empty ( Isolate * isolate )

static

A zero length string.

Definition at line 11675 of file v8.h.

References Internals::CheckInitialized(), Internals::GetRoot(), Internals::kEmptyStringRootIndex, and Local< T >::Local.

Referenced by String::NewFromUtf8Literal().

◆ GetExternalOneByteStringResource()

const ExternalOneByteStringResource* GetExternalOneByteStringResource ( ) const

Get the ExternalOneByteStringResource for an external one-byte string. Returns NULL if IsExternalOneByte() doesn't return true.

◆ GetExternalStringResource()

String::ExternalStringResource * GetExternalStringResource ( ) const

Get the ExternalStringResource for an external string. Returns NULL if IsExternal() doesn't return true.

Definition at line 11684 of file v8.h.

References Internals::GetInstanceType(), Internals::GetIsolateForHeapSandbox(), Internals::IsExternalTwoByteString(), v8::internal::kExternalStringResourceTag, Internals::kStringResourceOffset, and Internals::ReadExternalPointerField().

◆ GetExternalStringResourceBase()

String::ExternalStringResourceBase * GetExternalStringResourceBase ( String::Encoding * encoding_out ) const

If the string is an external string, return the ExternalStringResourceBase regardless of the encoding, otherwise return NULL. The encoding of the string is returned in encoding_out.

Definition at line 11706 of file v8.h.

References Internals::GetInstanceType(), Internals::GetIsolateForHeapSandbox(), Internals::kExternalOneByteRepresentationTag, v8::internal::kExternalStringResourceTag, Internals::kExternalTwoByteRepresentationTag, Internals::kFullStringRepresentationMask, Internals::kStringEncodingMask, Internals::kStringResourceOffset, and Internals::ReadExternalPointerField().

◆ IsExternal()

bool IsExternal ( ) const

Returns true if the string is external.

◆ IsExternalOneByte()

bool IsExternalOneByte ( ) const

Returns true if the string is both external and one-byte.

◆ IsExternalTwoByte()

bool IsExternalTwoByte ( ) const

Returns true if the string is both external and two-byte.

◆ IsOneByte()

bool IsOneByte ( ) const

Returns whether this string is known to contain only one byte data, i.e. ISO-8859-1 code points. Does not read the string. False negatives are possible.

◆ Length()

int Length ( ) const

Returns the number of characters (UTF-16 code units) in this string.

◆ MakeExternal() [1/2]

bool MakeExternal ( ExternalOneByteStringResource * resource )

Associate an external string resource with this string by transforming it in place so that existing references to this string in the JavaScript heap will use the external string resource. The external string resource's character contents need to be equivalent to this string. Returns true if the string has been changed to be an external string. The string is not modified if the operation fails. See NewExternal for information on the lifetime of the resource.

◆ MakeExternal() [2/2]

bool MakeExternal ( ExternalStringResource * resource )

Associate an external string resource with this string by transforming it in place so that existing references to this string in the JavaScript heap will use the external string resource. The external string resource's character contents need to be equivalent to this string. Returns true if the string has been changed to be an external string. The string is not modified if the operation fails. See NewExternal for information on the lifetime of the resource.

◆ NewExternalOneByte()

static V8_WARN_UNUSED_RESULT MaybeLocal<String> NewExternalOneByte	(	Isolate *	isolate,
		ExternalOneByteStringResource *	resource
	)

static

Creates a new external string using the one-byte data defined in the given resource. When the external string is no longer live on V8's heap the resource will be disposed by calling its Dispose method. The caller of this function should not otherwise delete or modify the resource. Neither should the underlying buffer be deallocated or modified except through the destructor of the external string resource.

◆ NewExternalTwoByte()

static V8_WARN_UNUSED_RESULT MaybeLocal<String> NewExternalTwoByte	(	Isolate *	isolate,
		ExternalStringResource *	resource
	)

static

Creates a new external string using the data defined in the given resource. When the external string is no longer live on V8's heap the resource will be disposed by calling its Dispose method. The caller of this function should not otherwise delete or modify the resource. Neither should the underlying buffer be deallocated or modified except through the destructor of the external string resource.

◆ NewFromOneByte()

static V8_WARN_UNUSED_RESULT MaybeLocal<String> NewFromOneByte	(	Isolate *	isolate,
		const uint8_t *	data,
		NewStringType	type = `NewStringType::kNormal`,
		int	length = `-1`
	)

static

Allocates a new string from Latin-1 data. Only returns an empty value when length > kMaxLength.

◆ NewFromTwoByte()

static V8_WARN_UNUSED_RESULT MaybeLocal<String> NewFromTwoByte	(	Isolate *	isolate,
		const uint16_t *	data,
		NewStringType	type = `NewStringType::kNormal`,
		int	length = `-1`
	)

static

Allocates a new string from UTF-16 data. Only returns an empty value when length > kMaxLength.

◆ NewFromUtf8()

static V8_WARN_UNUSED_RESULT MaybeLocal<String> NewFromUtf8	(	Isolate *	isolate,
		const char *	data,
		NewStringType	type = `NewStringType::kNormal`,
		int	length = `-1`
	)

static

Allocates a new string from UTF-8 data. Only returns an empty value when length > kMaxLength.

Referenced by Template::Set().

◆ NewFromUtf8Literal() [1/2]

V8_WARN_UNUSED_RESULT Local<String> NewFromUtf8Literal	(	Isolate *	isolate,
		const char(&)	literal[1],
		NewStringType	type
	)

inline

Definition at line 3642 of file v8.h.

References String::Empty().

◆ NewFromUtf8Literal() [2/2]

static V8_WARN_UNUSED_RESULT Local<String> NewFromUtf8Literal	(	Isolate *	isolate,
		const char(&)	literal[N],
		NewStringType	type = `NewStringType::kNormal`
	)

inlinestatic

Allocates a new string from a UTF-8 literal. This is equivalent to calling String::NewFromUtf(isolate, "...").ToLocalChecked(), but without the check overhead.

When called on a string literal containing '\0', the inferred length is the length of the input array minus 1 (for the final '\0') and not the value returned by strlen.

Definition at line 3491 of file v8.h.

References String::kMaxLength.

◆ StringEquals()

bool StringEquals ( Local< String > str ) const

Returns true if the strings values are equal. Same as JS ==/===.

◆ Utf8Length()

int Utf8Length ( Isolate * isolate ) const

Returns the number of bytes in the UTF-8 encoded representation of this string.

◆ Write()

int Write	(	Isolate *	isolate,
		uint16_t *	buffer,
		int	start = `0`,
		int	length = `-1`,
		int	options = `NO_OPTIONS`
	)		const

◆ WriteOneByte()

int WriteOneByte	(	Isolate *	isolate,
		uint8_t *	buffer,
		int	start = `0`,
		int	length = `-1`,
		int	options = `NO_OPTIONS`
	)		const

◆ WriteUtf8()

int WriteUtf8	(	Isolate *	isolate,
		char *	buffer,
		int	length = `-1`,
		int *	nchars_ref = `nullptr`,
		int	options = `NO_OPTIONS`
	)		const

Field Documentation

◆ kMaxLength

constexpr int kMaxLength

staticconstexpr

Initial value:

=

internal::kApiSystemPointerSize == 4 ? (1 << 28) - 16 : (1 << 29) - 24

v8::internal::kApiSystemPointerSize

const int kApiSystemPointerSize

Definition: v8-internal.h:35

Definition at line 3205 of file v8.h.

Referenced by String::NewFromUtf8Literal().

The documentation for this class was generated from the following file:

include/v8.h

Data Structures

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Detailed Description

Member Enumeration Documentation

◆ Encoding

◆ WriteOptions

Member Function Documentation

◆ CanMakeExternal()

◆ Cast()

◆ Concat()

◆ ContainsOnlyOneByte()

◆ Empty()

◆ GetExternalOneByteStringResource()

◆ GetExternalStringResource()

◆ GetExternalStringResourceBase()

◆ IsExternal()

◆ IsExternalOneByte()

◆ IsExternalTwoByte()

◆ IsOneByte()

◆ Length()

◆ MakeExternal() [1/2]

◆ MakeExternal() [2/2]

◆ NewExternalOneByte()

◆ NewExternalTwoByte()

◆ NewFromOneByte()

◆ NewFromTwoByte()

◆ NewFromUtf8()

◆ NewFromUtf8Literal() [1/2]

◆ NewFromUtf8Literal() [2/2]

◆ StringEquals()

◆ Utf8Length()

◆ Write()

◆ WriteOneByte()

◆ WriteUtf8()

Field Documentation

◆ kMaxLength