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::EscapableHandleScopeobject.
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() constReturns 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.