# Key Event

Name		Bubble Supported	Description
onKeyEvent(event: (event?: KeyEvent) => void)		Yes	Called when a key event occurs. For details about the event parameters, see KeyEvent Object.

## KeyEvent Object - Attributes

Name	Type	Description
type	KeyType	Type of a key.
keyCode	number	Key code.
keyText	string	Key value.
keySource	KeySource	Type of the input device that triggers the key event.
deviceId	number	ID of the input device that triggers the key event.
metaKey	number	State of the metakey when the key is pressed. The value 1 means the pressed state, and 0 means the unpressed state.
timestamp	number	Timestamp when the key is pressed.

- APIs

Name	Description
stopPropagation(): void	Stops the event from bubbling upwards or downwards.

- KeyType enums

Name	Description
Down	The key is pressed.
Up	The key is released.

- KeySource enums

Name	Description
Unknown	Unknown input device.
Keyboard	The input device is a keyboard.

- Common KeyCode description

Value	Behavior	Physical Button
19	Upward	Up button.
20	Downward	Down button.
21	Leftward	Left button.
22	Rightward	Right button.
23	OK	OK key on a remote control.
66	OK	Enter key on a keyboard.
160	OK	Enter button on the numeric keypad.

## Example ``` @Entry @Component struct KeyEventExample { @State text: string = '' @State eventType: string = '' build() { Column() { Button('KeyEvent').backgroundColor(0x2788D9) .onKeyEvent((event: KeyEvent) => { if (event.type === KeyType.Down) { this.eventType = 'Down' } if (event.type === KeyType.Up) { this.eventType = 'Up' } console.info(this.text = 'KeyType:' + this.eventType + '\nkeyCode:' + event.keyCode + '\nkeyText:' + event.keyText) }) Text(this.text).padding(15) }.height(300).width('100%').padding(35) } } ``` ![](figures/keyevent.gif)