2.6 KiB
EscapableHandleScope
The Napi::EscapableHandleScope
class is used to manage the lifetime of object handles
which are created through the use of node-addon-api. These handles
keep an object alive in the heap in order to ensure that the objects
are not collected by the garbage collector while native code is using them.
A handle may be created when any new node-addon-api Value or one
of its subclasses is created or returned.
The Napi::EscapableHandleScope
is a special type of Napi::HandleScope
which allows a single handle to be "promoted" to an outer scope.
For more details refer to the section titled Object lifetime management.
Methods
Constructor
Creates a new escapable handle scope.
Napi::EscapableHandleScope Napi::EscapableHandleScope::New(Napi:Env env);
[in] Env
: The environment in which to construct theNapi::EscapableHandleScope
object.
Returns a new Napi::EscapableHandleScope
Constructor
Creates a new escapable handle scope.
Napi::EscapableHandleScope Napi::EscapableHandleScope::New(napi_env env, napi_handle_scope scope);
[in] env
: napi_env in which the scope passed in was created.[in] scope
: pre-existing napi_handle_scope.
Returns a new Napi::EscapableHandleScope
instance which wraps the
napi_escapable_handle_scope handle passed in. This can be used
to mix usage of the C N-API and node-addon-api.
operator EscapableHandleScope::napi_escapable_handle_scope
operator Napi::EscapableHandleScope::napi_escapable_handle_scope() const
Returns the N-API napi_escapable_handle_scope wrapped by the Napi::EscapableHandleScope
object.
This can be used to mix usage of the C N-API and node-addon-api by allowing
the class to be used be converted to a napi_escapable_handle_scope.
Destructor
Napi::EscapableHandleScope::~EscapableHandleScope();
Deletes the Napi::EscapableHandleScope
instance and allows any objects/handles created
in the scope to be collected by the garbage collector. There is no
guarantee as to when the gargbage collector will do this.
Escape
napi::Value Napi::EscapableHandleScope::Escape(napi_value escapee);
[in] escapee
: Napi::Value or napi_env to promote to the outer scope
Returns Napi::Value
which can be used in the outer scope. This method can
be called at most once on a given Napi::EscapableHandleScope
. If it is called
more than once an exception will be thrown.
Env
Napi::Env Napi::EscapableHandleScope::Env() const;
Returns the Napi::Env
associated with the Napi::EscapableHandleScope
.