Inheritance diagram for xtd::delegate< result_t()>:

Definition

template<typename result_t>
class xtd::delegate< result_t()>

Represents a delegate, which is a data structure that refers to a static method or to a class instance and an instance method of that class.

Header: #include <xtd/delegate>

Namespace: xtd

Library: xtd.core

Remarks: For more info about delegates see Delegates guide.

Examples: The following example shows how to define a delegate named my Method delegate. Instances of this delegate are created for an instance method and a static method of the nested mySampleClass class. The delegate for the instance method requires an instance of mySampleClass. The mySampleClass instance is saved in a variable named mySC.
#include <xtd/xtd>

auto goodbye(const string& s) -> void {

console::write_line("Goodbye {}", s);

}

class object {

public:

auto hello(const string& s) -> void {

console::write_line("Hello {}", s);

}

};

auto main() -> int {

using example_function = delegate<void(const string&)>;

auto instance = ::object {};

auto str = string {"World"};

//equivanet to : example_function f = {std::bind(&::object::hello, &instance, std::placeholders::_1)};

auto f = example_function {instance, &::object::hello};

// equivalent to : instance.hello(str)

f(str);

f = goodbye;

// equivalent to : goodbye(str)

f(str);

return 0;

}

// This code produces the following output :

//

// Hello, World

// Goodbye, World

xtd::console::write_line
static auto write_line() -> void
Writes the current line terminator to the standard output stream using the specified format informati...

xtd::object
Supports all classes in the xtd class hierarchy and provides low-level services to derived classes....
Definition object.hpp:45

xtd::console_key::f
@ f
The F key.
Definition console_key.hpp:98

Public Aliases
using	function_t
	Represents function type.
using	function_collection
	Represents the function collection type.

Public Constructors
	delegate ()=default
	Initializes an empty delegate.
	delegate (const function_t &function) noexcept
	Initializes a delegate that invokes the specified instance method.
template<class object1_t, typename object2_t>
	delegate (const object1_t &object, result_t(object2_t::*method)() const) noexcept
	Initializes a delegate that invokes the specified instance method on the specified class instance.
template<class object1_t, typename object2_t>
	delegate (const object1_t &object, result_t(object2_t::*method)()) noexcept
	Initializes a delegate that invokes the specified instance method on the specified class instance.

Public Properties
auto	count () const noexcept -> xtd::usize
	Return the size of invocation list.
auto	functions () const -> const function_collection &
	Gets the delegates array.
auto	is_empty () const noexcept -> bool
	Return if the delegate is empty.
auto	size () const noexcept -> xtd::usize
	Return the size of invocation list.

Public Methods
auto	clear () -> void
	Clear delegates array.
auto	begin_invoke () -> async_result
	Executes the method represented by the current delegate asynchronously on the thread that the control's underlying handle was created on.
auto	begin_invoke (xtd::async_callback async_callback) -> async_result
	Executes the method represented by the current delegate asynchronously on the thread that the control's underlying handle was created on.
auto	begin_invoke (xtd::async_callback async_callback, const xtd::any_object &async_state) -> async_result
	Executes the method represented by the current delegate asynchronously on the thread that the control's underlying handle was created on.
auto	end_invoke (async_result async) -> result_t
	Retrieves the return value of the asynchronous operation represented by the async_result_invoke passed.
auto	invoke () const -> result_t
	invokes the method represented by the current delegate.
auto	equals (const object &obj) const noexcept -> bool override
	Determines whether this instance and another specified delegateType object have the same value.
auto	equals (const delegate &other) const noexcept -> bool override
	Determines whether this instance and another specified delegateType object have the same value.

Operators
auto	operator() () const -> result_t
	invokes the method represented by the current delegate.
auto	operator= (const function_t &function) noexcept -> delegate &

Public Static Methods
static auto	combine (const xtd::array< delegate > &delegates) noexcept -> delegate
	Concatenates the invocation lists of an array of delegates.
static auto	combine (const delegate &a, const delegate &b) noexcept -> delegate
	Concatenates the invocation lists of two delegates.
static auto	remove (const delegate &source, const delegate &value) noexcept -> delegate
	removes the last occurrence of the invocation list of a delegate from the invocation list of another delegate.
static auto	remove_all (const delegate &source, const delegate &value) noexcept -> delegate
	removes all occurrences of the invocation list of a delegate from the invocation list of another delegate.

Additional Inherited Members
	object ()=default
	Create a new instance of the ultimate base class object.
virtual xtd::usize	get_hash_code () const noexcept
	Serves as a hash function for a particular type.
virtual type_object	get_type () const noexcept
	Gets the type of the current instance.
template<typename object_t>
xtd::unique_ptr_object< object_t >	memberwise_clone () const
	Creates a shallow copy of the current object.
virtual xtd::string	to_string () const
	Returns a xtd::string that represents the current object.
virtual bool	equals (const delegate< result_t()> &) const noexcept=0
	Indicates whether the current object is equal to another object of the same type.
template<typename object_a_t, typename object_b_t>
static bool	equals (const object_a_t &object_a, const object_b_t &object_b) noexcept
	Determines whether the specified object instances are considered equal.
template<typename object_a_t, typename object_b_t>
static bool	reference_equals (const object_a_t &object_a, const object_b_t &object_b) noexcept
	Determines whether the specified object instances are the same instance.

Member Typedef Documentation

◆ function_t

template<typename result_t>

using xtd::delegate< result_t()>::function_t

Represents function type.

◆ function_collection

template<typename result_t>

using xtd::delegate< result_t()>::function_collection

Represents the function collection type.

Constructor & Destructor Documentation

◆ delegate() [1/4]

template<typename result_t>

xtd::delegate< result_t()>::delegate ( )

default

Initializes an empty delegate.

◆ delegate() [2/4]

template<typename result_t>

xtd::delegate< result_t()>::delegate ( const function_t & function )

inlinenoexcept

Initializes a delegate that invokes the specified instance method.

Parameters

function the method instance.

◆ delegate() [3/4]

template<typename result_t>

template<class object1_t, typename object2_t>

xtd::delegate< result_t()>::delegate	(	const object1_t &	object,
		result_t(object2_t::*	method )() const )

inlinenoexcept

Initializes a delegate that invokes the specified instance method on the specified class instance.

Parameters

object	the class instance.
function	the method instance.

◆ delegate() [4/4]

template<typename result_t>

template<class object1_t, typename object2_t>

xtd::delegate< result_t()>::delegate	(	const object1_t &	object,
		result_t(object2_t::*	method )() )

inlinenoexcept

Initializes a delegate that invokes the specified instance method on the specified class instance.

Parameters

object	the class instance.
function	the method instance.

Member Function Documentation

◆ count()

template<typename result_t>

auto xtd::delegate< result_t()>::count ( ) const -> xtd::usize

inlinenodiscardnoexcept

Return the size of invocation list.

Returns: Return the size of invocation list.

◆ functions()

template<typename result_t>

auto xtd::delegate< result_t()>::functions ( ) const -> const function_collection &

inlinenodiscard

Gets the delegates array.

Returns: The delegates array.

◆ is_empty()

template<typename result_t>

auto xtd::delegate< result_t()>::is_empty ( ) const -> bool

inlinenodiscardnoexcept

Return if the delegate is empty.

Returns: bool Return true if delegate is empty; otherwise false.

◆ size()

template<typename result_t>

auto xtd::delegate< result_t()>::size ( ) const -> xtd::usize

inlinenodiscardnoexcept

Return the size of invocation list.

Returns: Return the size of invocation list.

◆ clear()

template<typename result_t>

auto xtd::delegate< result_t()>::clear ( ) -> void

inline

Clear delegates array.

◆ begin_invoke() [1/3]

template<typename result_t>

auto xtd::delegate< result_t()>::begin_invoke ( ) -> async_result

nodiscard

Executes the method represented by the current delegate asynchronously on the thread that the control's underlying handle was created on.

Returns: An async_result_invoke that represents the result of the begin_invoke operation.

Examples: The following examples shows hot tu use xtd::delegate::begin_invoke, xtd::delegate::end_invoke, xtd::delegate::invoke methods.
#include <xtd/xtd>

auto main() -> int {

auto d1 = delegate<int(const string&)> {[](auto&& name) {

console::write_line("(Thread {}) Hello {}!", thread::current_thread().managed_thread_id(), name);

return name == "xtd" ? 42 : 24;

}};

auto result = d1.begin_invoke("Gammasoft");

console::write_line("return = {}", d1.invoke("xtd"));

console::write_line("return = {}", d1.end_invoke(result));

}

// This code produces the following output :

//

// (Thread 1) Hello xtd!

// return = 42

// (Thread 4) Hello Gammasoft!

// return = 24

xtd::delegate< result_t()>::delegate
delegate()=default
Initializes an empty delegate.

xtd::console_key::d1
@ d1
The 1 key.
Definition console_key.hpp:70

◆ begin_invoke() [2/3]

template<typename result_t>

auto xtd::delegate< result_t()>::begin_invoke ( xtd::async_callback async_callback ) -> async_result

nodiscard

Executes the method represented by the current delegate asynchronously on the thread that the control's underlying handle was created on.

Parameters

async_callback The asynchronous callback that will be called at the end of the invocation.

Returns: An async_result_invoke that represents the result of the begin_invoke operation.

Examples: The following examples shows hot tu use xtd::delegate::begin_invoke, xtd::delegate::end_invoke, xtd::delegate::invoke methods.
#include <xtd/xtd>

auto main() -> int {

auto d1 = delegate<int(const string&)> {[](auto&& name) {

console::write_line("(Thread {}) Hello {}!", thread::current_thread().managed_thread_id(), name);

return name == "xtd" ? 42 : 24;

}};

auto result = d1.begin_invoke("Gammasoft");

console::write_line("return = {}", d1.invoke("xtd"));

console::write_line("return = {}", d1.end_invoke(result));

}

// This code produces the following output :

//

// (Thread 1) Hello xtd!

// return = 42

// (Thread 4) Hello Gammasoft!

// return = 24

◆ begin_invoke() [3/3]

template<typename result_t>

auto xtd::delegate< result_t()>::begin_invoke	(	xtd::async_callback	async_callback,
		const xtd::any_object &	async_state ) -> async_result

nodiscard

Executes the method represented by the current delegate asynchronously on the thread that the control's underlying handle was created on.

Parameters

async_callback	The asynchronous callback that will be called at the end of the invocation.
async_state	The asynchronous state associated with the invocation.

Returns: An async_result_invoke that represents the result of the begin_invoke operation.

Examples: The following examples shows hot tu use xtd::delegate::begin_invoke, xtd::delegate::end_invoke, xtd::delegate::invoke methods.
#include <xtd/xtd>

auto main() -> int {

auto d1 = delegate<int(const string&)> {[](auto&& name) {

console::write_line("(Thread {}) Hello {}!", thread::current_thread().managed_thread_id(), name);

return name == "xtd" ? 42 : 24;

}};

auto result = d1.begin_invoke("Gammasoft");

console::write_line("return = {}", d1.invoke("xtd"));

console::write_line("return = {}", d1.end_invoke(result));

}

// This code produces the following output :

//

// (Thread 1) Hello xtd!

// return = 42

// (Thread 4) Hello Gammasoft!

// return = 24

◆ end_invoke()

template<typename result_t>

auto xtd::delegate< result_t()>::end_invoke ( async_result async ) -> result_t

Retrieves the return value of the asynchronous operation represented by the async_result_invoke passed.

Parameters

async The async_result_invoke that represents a specific invoke asynchronous operation, returned when calling begin_invoke.

Examples: The following examples shows hot tu use xtd::delegate::begin_invoke, xtd::delegate::end_invoke, xtd::delegate::invoke methods.
#include <xtd/xtd>

auto main() -> int {

auto d1 = delegate<int(const string&)> {[](auto&& name) {

console::write_line("(Thread {}) Hello {}!", thread::current_thread().managed_thread_id(), name);

return name == "xtd" ? 42 : 24;

}};

auto result = d1.begin_invoke("Gammasoft");

console::write_line("return = {}", d1.invoke("xtd"));

console::write_line("return = {}", d1.end_invoke(result));

}

// This code produces the following output :

//

// (Thread 1) Hello xtd!

// return = 42

// (Thread 4) Hello Gammasoft!

// return = 24

◆ invoke()

template<typename result_t>

auto xtd::delegate< result_t()>::invoke ( ) const -> result_t

inline

invokes the method represented by the current delegate.

Parameters

arguments The parameter list.

Returns: result_t The return value.

Examples: The following examples shows hot tu use xtd::delegate::begin_invoke, xtd::delegate::end_invoke, xtd::delegate::invoke methods.
#include <xtd/xtd>

auto main() -> int {

auto d1 = delegate<int(const string&)> {[](auto&& name) {

console::write_line("(Thread {}) Hello {}!", thread::current_thread().managed_thread_id(), name);

return name == "xtd" ? 42 : 24;

}};

auto result = d1.begin_invoke("Gammasoft");

console::write_line("return = {}", d1.invoke("xtd"));

console::write_line("return = {}", d1.end_invoke(result));

}

// This code produces the following output :

//

// (Thread 1) Hello xtd!

// return = 42

// (Thread 4) Hello Gammasoft!

// return = 24

◆ equals() [1/2]

template<typename result_t>

auto xtd::delegate< result_t()>::equals ( const object & obj ) const -> bool

inlinenodiscardoverridevirtualnoexcept

Determines whether this instance and another specified delegateType object have the same value.

Parameters

obj	The delegateType to compare.

Returns: bool true if the value of this instance is the same as the value of value; otherwise, false.

Reimplemented from xtd::object.

◆ equals() [2/2]

template<typename result_t>

auto xtd::delegate< result_t()>::equals ( const delegate< result_t()> & other ) const -> bool

inlinenodiscardoverridenoexcept

Determines whether this instance and another specified delegateType object have the same value.

Parameters

other The delegateType to compare.

Returns: bool true if the value of this instance is the same as the value of value; otherwise, false.

◆ combine() [1/2]

template<typename result_t>

auto xtd::delegate< result_t()>::combine ( const xtd::array< delegate< result_t()> > & delegates ) -> delegate

inlinestaticnodiscardnoexcept

Concatenates the invocation lists of an array of delegates.

Parameters

delegates The array of delegates to combine.

Returns: Delegate A new delegate with an invocation list that concatenates the invocation lists of the delegates in the delegates array. Returns null if delegates is null, if delegates contains zero elements, or if every entry in delegates is null.

Remarks: If the delegates array contains entries that are null, those entries are ignored.; The invocation list can contain duplicate entries; that is, entries that refer to the same method on the same object.

◆ combine() [2/2]

template<typename result_t>

auto xtd::delegate< result_t()>::combine	(	const delegate< result_t()> &	a,
		const delegate< result_t()> &	b ) -> delegate

inlinestaticnodiscardnoexcept

Concatenates the invocation lists of two delegates.

Parameters

a	The delegate whose invocation list comes first.
b	The delegate whose invocation list comes second.

Returns: A new delegate with an invocation list that concatenates the invocation lists of a and b in that order. Returns a if b is empty, returns b if a is a empty, and returns empty if both a and b are empty.

Remarks: The invocation list can contain duplicate entries; that is, entries that refer to the same method on the same object.

◆ remove()

template<typename result_t>

auto xtd::delegate< result_t()>::remove	(	const delegate< result_t()> &	source,
		const delegate< result_t()> &	value ) -> delegate

inlinestaticnodiscardnoexcept

removes the last occurrence of the invocation list of a delegate from the invocation list of another delegate.

Parameters

source	The delegate from which to remove the invocation list of value.
value	The delegate that supplies the invocation list to remove from the invocation list of source.

Returns: A new delegate with an invocation list formed by taking the invocation list of source and removing the last occurrence of the invocation list of value, if the invocation list of value is found within the invocation list of source. Returns source if value is null or if the invocation list of value is not found within the invocation list of source. Returns a null reference if the invocation list of value is equal to the invocation list of source or if source is a null reference.

Remarks: If the invocation list of value matches a contiguous set of elements in the invocation list of source, then the invocation list of value is said to occur within the invocation list of source. If the invocation list of value occurs more than once in the invocation list of source, the last occurrence is removed.

◆ remove_all()

template<typename result_t>

auto xtd::delegate< result_t()>::remove_all	(	const delegate< result_t()> &	source,
		const delegate< result_t()> &	value ) -> delegate

inlinestaticnodiscardnoexcept

removes all occurrences of the invocation list of a delegate from the invocation list of another delegate.

Parameters

source	The delegate from which to remove the invocation list of value.
value	The delegate that supplies the invocation list to remove from the invocation list of source.

Returns: A new delegate with an invocation list formed by taking the invocation list of source and removing all occurrences of the invocation list of value, if the invocation list of value is found within the invocation list of source. Returns source if value is null or if the invocation list of value is not found within the invocation list of source. Returns a null reference if the invocation list of value is equal to the invocation list of source, if source contains only a series of invocation lists that are equal to the invocation list of value, or if source is a null reference.

Remarks: If the invocation list of value matches a contiguous set of elements in the invocation list of source, then the invocation list of value is said to occur within the invocation list of source. If the invocation list of value occurs more than once in the invocation list of source, all occurrences are removed.

◆ operator()()

template<typename result_t>

auto xtd::delegate< result_t()>::operator() ( ) const -> result_t

inline

invokes the method represented by the current delegate.

Parameters

arguments The parameter list.

Returns: result_t The return value.

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

xtd.core/include/xtd/delegate.hpp

Definition

Public Aliases

Public Constructors

Public Properties

Public Methods

Operators

Public Static Methods

Additional Inherited Members

Member Typedef Documentation

◆ function_t

◆ function_collection

Constructor & Destructor Documentation

◆ delegate() [1/4]

◆ delegate() [2/4]

◆ delegate() [3/4]

◆ delegate() [4/4]

Member Function Documentation

◆ count()

◆ functions()

◆ is_empty()

◆ size()

◆ clear()

◆ begin_invoke() [1/3]

◆ begin_invoke() [2/3]

◆ begin_invoke() [3/3]

◆ end_invoke()

◆ invoke()

◆ equals() [1/2]

◆ equals() [2/2]

◆ combine() [1/2]

◆ combine() [2/2]

◆ remove()

◆ remove_all()

◆ operator()()