7.9 KiB
FunctionReference
Napi::FunctionReference is a subclass of Napi::Reference, and is equivalent
to an instance of Napi::Reference<Napi::Function>.
This means that a Napi::FunctionReference holds a Napi::Function, and a count of the
number of references to that Napi::Function. When the count
is greater than 0, a Napi::FunctionReference is not
eligible for garbage collection. This ensures that the
Function will remain accessible, even if the original
reference to it is no longer available.
Napi::FunctionReference allows the referenced JavaScript
function object to be called from a native add-on with two different
methods: Call and MakeCallback. See the
documentation for Napi::Function
for when Call should be used instead of
MakeCallback and vice-versa.
The Napi::FunctionReference class inherits its behavior
from the Napi::Reference class (for more info see: Napi::Reference).
Methods
Weak
Creates a “weak” reference to the value, in that the initial reference count is set to 0.
static Napi::FunctionReference Napi::Weak(const Napi::Function& value);[in] value: The value which is to be referenced.
Returns the newly created reference.
Persistent
Creates a “persistent” reference to the value, in that the initial reference count is set to 1.
static Napi::FunctionReference Napi::Persistent(const Napi::Function& value);[in] value: The value which is to be referenced.
Returns the newly created reference.
Constructor
Creates a new empty instance of
Napi::FunctionReference.
Napi::FunctionReference::FunctionReference();Constructor
Creates a new instance of the
Napi::FunctionReference.
Napi::FunctionReference::FunctionReference(napi_env env, napi_ref ref);[in] env: The environment in which to construct theNapi::FunctionReferenceobject.[in] ref: The N-API reference to be held by theNapi::FunctionReference.
Returns a newly created Napi::FunctionReference
object.
New
Constructs a new instance by calling the constructor held by this reference.
Napi::Object Napi::FunctionReference::New(const std::initializer_list<napi_value>& args) const;[in] args: Initializer list of JavaScript values asnapi_valuerepresenting the arguments of the contructor function.
Returns a new JavaScript object.
New
Constructs a new instance by calling the constructor held by this reference.
Napi::Object Napi::FunctionReference::New(const std::vector<napi_value>& args) const;[in] args: Vector of JavaScript values asnapi_valuerepresenting the arguments of the constructor function.
Returns a new JavaScript object.
Call
Calls a referenced Javascript function from a native add-on.
Napi::Value Napi::FunctionReference::Call(const std::initializer_list<napi_value>& args) const;[in] args: Initializer list of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
Call
Calls a referenced JavaScript function from a native add-on.
Napi::Value Napi::FunctionReference::Call(const std::vector<napi_value>& args) const;[in] args: Vector of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
Call
Calls a referenced JavaScript function from a native add-on.
Napi::Value Napi::FunctionReference::Call(napi_value recv, const std::initializer_list<napi_value>& args) const;[in] recv: Thethisobject passed to the referenced function when it’s called.[in] args: Initializer list of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
Call
Calls a referenced JavaScript function from a native add-on.
Napi::Value Napi::FunctionReference::Call(napi_value recv, const std::vector<napi_value>& args) const;[in] recv: Thethisobject passed to the referenced function when it’s called.[in] args: Vector of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
Call
Calls a referenced JavaScript function from a native add-on.
Napi::Value Napi::FunctionReference::Call(napi_value recv, size_t argc, const napi_value* args) const;[in] recv: Thethisobject passed to the referenced function when it’s called.[in] argc: The number of arguments passed to the referenced function.[in] args: Array of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
MakeCallback
Calls a referenced JavaScript function from a native add-on after an asynchronous operation.
Napi::Value Napi::FunctionReference::MakeCallback(napi_value recv, const std::initializer_list<napi_value>& args, napi_async_context = nullptr) const;[in] recv: Thethisobject passed to the referenced function when it’s called.[in] args: Initializer list of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.[in] context: Context for the async operation that is invoking the callback. This should normally be a value previously obtained from Napi::AsyncContext. Howevernullptris also allowed, which indicates the current async context (if any) is to be used for the callback.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
MakeCallback
Calls a referenced JavaScript function from a native add-on after an asynchronous operation.
Napi::Value Napi::FunctionReference::MakeCallback(napi_value recv, const std::vector<napi_value>& args, napi_async_context context = nullptr) const;[in] recv: Thethisobject passed to the referenced function when it’s called.[in] args: Vector of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.[in] context: Context for the async operation that is invoking the callback. This should normally be a value previously obtained from Napi::AsyncContext. Howevernullptris also allowed, which indicates the current async context (if any) is to be used for the callback.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
MakeCallback
Calls a referenced JavaScript function from a native add-on after an asynchronous operation.
Napi::Value Napi::FunctionReference::MakeCallback(napi_value recv, size_t argc, const napi_value* args, napi_async_context context = nullptr) const;[in] recv: Thethisobject passed to the referenced function when it’s called.[in] argc: The number of arguments passed to the referenced function.[in] args: Array of JavaScript values asnapi_valuerepresenting the arguments of the referenced function.[in] context: Context for the async operation that is invoking the callback. This should normally be a value previously obtained from Napi::AsyncContext. Howevernullptris also allowed, which indicates the current async context (if any) is to be used for the callback.
Returns a Napi::Value representing the JavaScript object
returned by the referenced function.
Operator
Napi::Value operator ()(const std::initializer_list<napi_value>& args) const;[in] args: Initializer list of reference to JavaScript values asnapi_value
Returns a Napi::Value representing the JavaScript value
returned by the referenced function.