xtd::forms::key_event_args Class Reference

Inheritance diagram for xtd::forms::key_event_args:

Definition

Provides data for the xtd::forms::control::key_down or xtd::forms::control::key_up event.

Header

#include <xtd/forms/key_event_args>

Namespace

xtd::forms

Library

xtd.forms

Remarks

A key_event_args, which specifies the key the user pressed and whether any modifier keys (CMD, CTRL, ALT, and SHIFT) were pressed at the same time, is passed with each xtd::forms::control::key_down or xtd::forms::control::key_up event.

The xtd::forms::control::key_down event occurs when the user presses any key. The xtd::forms::control::key_up event occurs when the user releases the key. Duplicate xtd::forms::control::key_down events occur each time the key repeats, if the key is held down, but only one xtd::forms::control::key_up event is generated when the user releases the key.

The xtd::forms::control::key_press event also occurs when a key is pressed. A xtd::forms::key_press_event_args is passed with each xtd::forms::control::key_press event, and specifies the character that was composed as a result of each key press.

Examples

form_show.cpp, key_events.cpp, and test_forms.cpp.

Public Constructors
	key_event_args ()=default
	Initializes a new instance of the key_event_args class.
	key_event_args (xtd::forms::keys key_data)
	Initializes a new instance of the key_event_args class.

Public Properties
bool	alt () const noexcept
	Gets a value indicating whether the ALT key was pressed.
bool	command () const noexcept
	Gets a value indicating whether the CMD key was pressed.
bool	control () const noexcept
	Gets a value indicating whether the CTRL key was pressed.
bool	handled () const noexcept
	Gets a value indicating whether the event was handled.
void	handled (bool handled)
	Sets a value indicating whether the event was handled.
keys	key_code () const noexcept
	Gets the keyboard code for a xtd::forms::control::key_down or xtd::forms::control::key_up event.
keys	key_data () const noexcept
	Gets the key data for a xtd::forms::control::key_down or xtd::forms::control::key_up event.
int32	key_value () const noexcept
	Gets the keyboard value for a xtd::forms::control::key_down or xtd::forms::control::key_up event.
keys	modifiers () const noexcept
	Gets the modifier flags for a xtd::forms::control::key_down or xtd::forms::control::key_up event. The flags indicate which combination of CMD, CTRL, SHIFT, and ALT keys was pressed.
bool	shift () const noexcept
	Gets a value indicating whether the SHIFT key was pressed.
bool	suppress_key_press () const noexcept
	Gets a value indicating whether the key event should be passed on to the underlying control.
void	suppress_key_press (bool suppress_key_press)
	Sets a value indicating whether the key event should be passed on to the underlying control.

Additional Inherited Members
Static Public Attributes inherited from xtd::event_args
static const event_args	empty
	Provides a value to use with events that do not have event data.
Public Member Functions inherited from xtd::event_args
	event_args ()=default
	Initializes a new instance of the event_args class.
Public Member Functions inherited from xtd::object
	object ()=default
	Create a new instance of the ultimate base class object.
virtual bool	equals (const object &obj) const noexcept
	Determines whether the specified object is equal to the current object.
virtual size_t	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::uptr< object_t >	memberwise_clone () const
	Creates a shallow copy of the current object.
virtual xtd::string	to_string () const noexcept
	Returns a xtd::string that represents the current object.
Static Public Member Functions inherited from xtd::object
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.

Constructor & Destructor Documentation

key_event_args() [1/2]

xtd::forms::key_event_args::key_event_args ( )

default

Initializes a new instance of the key_event_args class.

key_event_args() [2/2]

xtd::forms::key_event_args::key_event_args ( xtd::forms::keys  key_data )

inlineexplicit

Initializes a new instance of the key_event_args class.

Parameters

key_data

A xtd::forms::keys representing the key that was pressed, combined with any modifier flags that indicate which CMD, CTRL, SHIFT, and ALT keys were pressed at the same time. Possible values are obtained by applying the bitwise OR (|) operator to constants from the Keys enumeration.

Member Function Documentation

alt()

bool xtd::forms::key_event_args::alt ( ) const

inlinenoexcept

Gets a value indicating whether the ALT key was pressed.

Returns

true if the ALT key was pressed; otherwise, false.

command()

bool xtd::forms::key_event_args::command ( ) const

inlinenoexcept

Gets a value indicating whether the CMD key was pressed.

Returns

true if the CMD key was pressed; otherwise, false.

control()

bool xtd::forms::key_event_args::control ( ) const

inlinenoexcept

Gets a value indicating whether the CTRL key was pressed.

Returns

true if the CTRL key was pressed; otherwise, false.

handled() [1/2]

bool xtd::forms::key_event_args::handled ( ) const

inlinenoexcept

Gets a value indicating whether the event was handled.

Returns

true to bypass the control's default handling; otherwise, false to also pass the event along to the default control handler.

Remarks

handled is implemented differently by different controls within xtd.forms. For controls like text_box which subclass native Win32 controls, it is interpreted to mean that the key message should not be passed to the underlying native control. If you set handled to true on a text_box, that control will not pass the key press events to the underlying Win32 text box control, but it will still display the characters that the user typed.

handled() [2/2]

void xtd::forms::key_event_args::handled ( bool  handled )

inline

Sets a value indicating whether the event was handled.

Parameters

handled

true to bypass the control's default handling; otherwise, false to also pass the event along to the default control handler.

Remarks

handled is implemented differently by different controls within xtd.forms. For controls like text_box which subclass native Win32 controls, it is interpreted to mean that the key message should not be passed to the underlying native control. If you set handled to true on a text_box, that control will not pass the key press events to the underlying Win32 text box control, but it will still display the characters that the user typed.

key_code()

keys xtd::forms::key_event_args::key_code ( ) const

inlinenoexcept

Gets the keyboard code for a xtd::forms::control::key_down or xtd::forms::control::key_up event.

Returns

A xtd::forms::keys value that is the key code for the event.

key_data()

keys xtd::forms::key_event_args::key_data ( ) const

inlinenoexcept

Gets the key data for a xtd::forms::control::key_down or xtd::forms::control::key_up event.

Returns

A xtd::forms::keys representing the key code for the key that was pressed, combined with modifier flags that indicate which combination of CMD, CTRL, SHIFT, and ALT keys was pressed at the same time.

Remarks

You can use constants from Keys to extract information from the key_data property. Use the bitwise AND operator to compare data returned by key_data with constants in Keys to obtain information about which keys the user pressed. To determine whether a specific modifier key was pressed, use the command, control, shift, and alt properties.

key_value()

int32 xtd::forms::key_event_args::key_value ( ) const

inlinenoexcept

Gets the keyboard value for a xtd::forms::control::key_down or xtd::forms::control::key_up event.

Returns

The integer representation of the key_code property.

modifiers()

keys xtd::forms::key_event_args::modifiers ( ) const

inlinenoexcept

Gets the modifier flags for a xtd::forms::control::key_down or xtd::forms::control::key_up event. The flags indicate which combination of CMD, CTRL, SHIFT, and ALT keys was pressed.

Returns

A xtd::forms::keys value representing one or more modifier flags.

shift()

bool xtd::forms::key_event_args::shift ( ) const

inlinenoexcept

Gets a value indicating whether the SHIFT key was pressed.

Returns

true if the SHIFT key was pressed; otherwise, false.

suppress_key_press() [1/2]

bool xtd::forms::key_event_args::suppress_key_press ( ) const

inlinenoexcept

Gets a value indicating whether the key event should be passed on to the underlying control.

Returns

true if the key event should not be sent to the control; otherwise, false.

Remarks

You can assign true to this property in an event handler such as xtd::forms::control::key_down in order to prevent user input.

Setting suppress_key_press to true also sets handled to true.

suppress_key_press() [2/2]

void xtd::forms::key_event_args::suppress_key_press ( bool  suppress_key_press )

inline

Sets a value indicating whether the key event should be passed on to the underlying control.

Parameters

suppress_key_press

true if the key event should not be sent to the control; otherwise, false.

Remarks

You can assign true to this property in an event handler such as xtd::forms::control::key_down in order to prevent user input.

Setting suppress_key_press to true also sets handled to true.

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

• xtd.forms/include/xtd/forms/key_event_args.h