js-apis-application-abilityConstant.md

# AbilityConstant

> **NOTE**<br>
> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.


Provides parameters related to ability launch.


## Modules to Import


```js
import AbilityConstant from '@ohos.application.AbilityConstant';
```


## Attributes

**System capability**: SystemCapability.Ability.AbilityRuntime.Core

 | Name | Type | Readable | Writable | Description | 
 | -------- | -------- | -------- | -------- | -------- |
 | launchReason | LaunchReason | Yes | Yes | Ability launch reason. | 
 | lastExitReason | LastExitReason | Yes | Yes | Reason for the last exit. | 

## AbilityConstant.LaunchReason

Enumerates ability launch reasons.

**System capability**: SystemCapability.Ability.AbilityRuntime.Core

 | Name | Value | Description |
 | ----------------------------- | ---- | ------------------------------------------------------------ |
 | UNKNOWN | 0 | Unknown reason. |
 | START_ABILITY | 1 | Ability startup. |
 | CALL | 2 | Call. |
 | CONTINUATION | 3 | Ability continuation. |


## AbilityConstant.LastExitReason

Enumerates reasons for the last exit.

**System capability**: SystemCapability.Ability.AbilityRuntime.Core

 | Name | Value | Description |
 | ----------------------------- | ---- | ------------------------------------------------------------ |
 | UNKNOWN | 0 | Unknown reason. |
 | ABILITY_NOT_RESPONDING | 1 | The ability does not respond. |
 | NORMAL | 2 | Normal status. |


## AbilityConstant.OnContinueResult 

Enumerates ability continuation results.

**System capability**: SystemCapability.Ability.AbilityRuntime.Core

 | Name | Value | Description |
 | ----------------------------- | ---- | ------------------------------------------------------------ |
 | AGREE | 0 | Continuation agreed. |
 | REJECT | 1 | Continuation denied. |
 | MISMATCH | 2 | Mismatch. |