2.9 KiB
Reference (template)
Holds a counted reference to a Napi::Value
object; initially a weak
reference unless otherwise specified, may be changed to/from a strong
reference by adjusting the refcount.
The referenced Napi::Value
is not immediately destroyed
when the reference count is zero; it is merely then eligible for
garbage-collection if there are no other references to the
Napi::Value
.
Napi::Reference
objects allocated in static space, such
as a global static instance, must call the SuppressDestruct
method to prevent its destructor, running at program shutdown time, from
attempting to reset the reference when the environment is no longer
valid.
The following classes inherit, either directly or indirectly, from
Napi::Reference
:
Methods
Factory Method
static Napi::Reference<T> Napi::Reference::New(const T& value, uint32_t initialRefcount = 0);
[in] value
: The value which is to be referenced.[in] initialRefcount
: The initial reference count.
Empty Constructor
::Reference::Reference(); Napi
Creates a new empty Napi::Reference
instance.
Constructor
::Reference::Reference(napi_env env, napi_value value); Napi
[in] env
: Thenapi_env
environment in which to construct theNapi::Reference
object.[in] value
: The N-API primitive value to be held by theNapi::Reference
.
Env
::Env Napi::Reference::Env() const; Napi
Returns the Napi::Env
value in which the
Napi::Reference
was instantiated.
IsEmpty
bool Napi::Reference::IsEmpty() const;
Determines whether the value held by the Napi::Reference
is empty.
Value
::Reference::Value() const; T Napi
Returns the value held by the Napi::Reference
.
Ref
uint32_t Napi::Reference::Ref();
Increments the reference count for the Napi::Reference
and returns the resulting reference count. Throws an error if the
increment fails.
Unref
uint32_t Napi::Reference::Unref();
Decrements the reference count for the Napi::Reference
and returns the resulting reference count. Throws an error if the
decrement fails.
Reset (Empty)
void Napi::Reference::Reset();
Sets the value held by the Napi::Reference
to be
empty.
Reset
void Napi::Reference::Reset(const T& value, uint32_t refcount = 0);
[in] value
: The value which is to be referenced.[in] initialRefcount
: The initial reference count.
Sets the value held by the Napi::Reference
.
SuppressDestruct
void Napi::Reference::SuppressDestruct();
Call this method on a Napi::Reference
that is declared
as static data to prevent its destructor, running at program shutdown
time, from attempting to reset the reference when the environment is no
longer valid.