1# @ohos.multimodalInput.inputEventClient (Key Event Injection) 2 3The **inputEventClient** module implements injection of key events. 4 5> **NOTE** 6> - The initial APIs of this module are supported since API version 8. Newly added APIs will be marked with a superscript to indicate their earliest API version. 7> - The APIs provided by this module are system APIs. 8 9 10## Modules to Import 11 12 13```js 14import inputEventClient from '@ohos.multimodalInput.inputEventClient'; 15``` 16 17 18## inputEventClient.injectEvent 19 20injectEvent({KeyEvent: KeyEvent}): void 21 22Injects a key event. Currently, key injection is supported only for the **Back** key (key value 2). 23 24**System capability**: SystemCapability.MultimodalInput.Input.InputSimulator 25 26**Parameters** 27 28| Name | Type | Mandatory | Description | 29| -------- | --------------------- | ---- | --------- | 30| KeyEvent | [KeyEvent](#keyevent) | Yes | Information about the key event to inject.| 31 32**Example** 33 34```js 35try { 36 let backKeyDown = { 37 isPressed: true, 38 keyCode: 2, 39 keyDownDuration: 0, 40 isIntercepted: false 41 } 42 inputEventClient.injectEvent({ KeyEvent: backKeyDown }); 43 44 let backKeyUp = { 45 isPressed: false, 46 keyCode: 2, 47 keyDownDuration: 0, 48 isIntercepted: false 49 }; 50 inputEventClient.injectEvent({ KeyEvent: backKeyUp }); 51} catch (error) { 52 console.log(`Failed to inject KeyEvent, error: ${JSON.stringify(error, [`code`, `message`])}`); 53} 54``` 55 56 57## KeyEvent 58 59Represents information about the key event to inject. 60 61**System capability**: SystemCapability.MultimodalInput.Input.InputSimulator 62 63| Name | Type | Readable | Writable | Description | 64| --------- | ------ | ---- | ---- | ------- | 65| isPressed | boolean | Yes | No| Whether the key is pressed. | 66| keyCode | number | Yes | No| Key value. Currently, only the **Back** key is supported.| 67| keyDownDuration | number | Yes | No| Duration within which the key is pressed. | 68| isIntercepted | boolean | Yes | No| Whether the key can be intercepted. | 69