Context Class Reference

#include <v8.h>

Data Structures
class	Scope

Public Member Functions
Local< Object >	Global ()
void	DetachGlobal ()
void	ReattachGlobal (Handle< Object > global_object)
void	SetSecurityToken (Handle< Value > token)
void	UseDefaultSecurityToken ()
Handle< Value >	GetSecurityToken ()
void	Enter ()
void	Exit ()
bool	HasOutOfMemoryException ()
void	SetData (Handle< Value > data)
Local< Value >	GetData ()
void	AllowCodeGenerationFromStrings (bool allow)
bool	IsCodeGenerationFromStringsAllowed ()
void	SetErrorMessageForCodeGenerationFromStrings (Handle< String > message)

Static Public Member Functions
static Persistent< Context >	New (ExtensionConfiguration *extensions=NULL, Handle< ObjectTemplate > global_template=Handle< ObjectTemplate >(), Handle< Value > global_object=Handle< Value >())
static Local< Context >	GetEntered ()
static Local< Context >	GetCurrent ()
static Local< Context >	GetCalling ()
static bool	InContext ()

Friends
class	Value
class	Script
class	Object
class	Function

Detailed Description

A sandboxed execution context with its own set of built-in objects and functions.

Definition at line 3635 of file v8.h.

Member Function Documentation

AllowCodeGenerationFromStrings()

void AllowCodeGenerationFromStrings

(

bool

allow

)

Control whether code generation from strings is allowed. Calling this method with false will disable 'eval' and the 'Function' constructor for code running in this context. If 'eval' or the 'Function' constructor are used an exception will be thrown.

If code generation from strings is not allowed the V8::AllowCodeGenerationFromStrings callback will be invoked if set before blocking the call to 'eval' or the 'Function' constructor. If that callback returns true, the call will be allowed, otherwise an exception will be thrown. If no callback is set an exception will be thrown.

DetachGlobal()

void DetachGlobal

(

)

Detaches the global object from its context before the global object can be reused to create a new context.

Enter()

void Enter

(

)

Enter this context. After entering a context, all code compiled and run is compiled and run in this context. If another context is already entered, this old context is saved so it can be restored when the new context is exited.

Referenced by Context::Scope::Scope().

Exit()

void Exit

(

)

Exit this context. Exiting the current context restores the context that was in place when entering the current context.

Referenced by Context::Scope::~Scope().

GetCalling()

static Local<Context> GetCalling ( )

static

Returns the context of the calling JavaScript code. That is the context of the top-most JavaScript frame. If there are no JavaScript frames an empty handle is returned.

GetCurrent()

static Local<Context> GetCurrent ( )

static

Returns the context that is on the top of the stack.

GetData()

Local<Value> GetData

(

)

GetEntered()

static Local<Context> GetEntered ( )

static

Returns the last entered context.

GetSecurityToken()

Handle<Value> GetSecurityToken

(

)

Returns the security token of this context.

Global()

Local<Object> Global

(

)

Returns the global proxy object or global object itself for detached contexts.

Global proxy object is a thin wrapper whose prototype points to actual context's global object with the properties like Object, etc. This is done that way for security reasons (for more details see https://wiki.mozilla.org/Gecko:SplitWindow).

Please note that changes to global proxy object prototype most probably would break VM—v8 expects only global object as a prototype of global proxy object.

If DetachGlobal() has been invoked, Global() would return actual global object until global is reattached with ReattachGlobal().

HasOutOfMemoryException()

bool HasOutOfMemoryException

(

)

Returns true if the context has experienced an out of memory situation.

InContext()

static bool InContext ( )

static

Returns true if V8 has a current context.

IsCodeGenerationFromStringsAllowed()

bool IsCodeGenerationFromStringsAllowed

(

)

Returns true if code generation from strings is allowed for the context. For more details see AllowCodeGenerationFromStrings(bool) documentation.

New()

static Persistent<Context> New ( ExtensionConfiguration *  extensions = NULL, Handle< ObjectTemplate >  global_template = Handle< ObjectTemplate >(), Handle< Value >  global_object = Handle< Value >()  )

static

Creates a new context.

Returns a persistent handle to the newly allocated context. This persistent handle has to be disposed when the context is no longer used so the context can be garbage collected.

Parameters

extensions	An optional extension configuration containing the extensions to be installed in the newly created context.
global_template	An optional object template from which the global object for the newly created context will be created.
global_object	An optional global object to be reused for the newly created context. This global object must have been created by a previous call to Context::New with the same global template. The state of the global object will be completely reset and only object identify will remain.

ReattachGlobal()

void ReattachGlobal

(

Handle< Object >

global_object

)

Reattaches a global object to a context. This can be used to restore the connection between a global object and a context after DetachGlobal has been called.

Parameters

global_object

The global object to reattach to the context. For this to work, the global object must be the global object that was associated with this context before a call to DetachGlobal.

SetData()

void SetData

(

Handle< Value >

data

)

Associate an additional data object with the context. This is mainly used with the debugger to provide additional information on the context through the debugger API.

SetErrorMessageForCodeGenerationFromStrings()

void SetErrorMessageForCodeGenerationFromStrings

(

Handle< String >

message

)

Sets the error description for the exception that is thrown when code generation from strings is not allowed and 'eval' or the 'Function' constructor are called.

SetSecurityToken()

void SetSecurityToken

(

Handle< Value >

token

)

Sets the security token for the context. To access an object in another context, the security tokens must match.

UseDefaultSecurityToken()

void UseDefaultSecurityToken

(

)

Restores the security token to the default value.

Friends And Related Function Documentation

Function

friend class Function

friend

Definition at line 3795 of file v8.h.

Object

friend class Object

friend

Definition at line 3794 of file v8.h.

Script

friend class Script

friend

Definition at line 3793 of file v8.h.

Value

friend class Value

friend

Definition at line 3792 of file v8.h.

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

• include/v8.h