# 延迟任务调度回调 > ![icon-note.gif](public_sys-resources/icon-note.gif) **说明:** > 本模块首批接口从API version 9开始支持。后续版本的新增接口,采用上角标单独标记接口的起始版本。 ## 导入模块 ``` import WorkSchedulerExtensionAbility from '@ohos.WorkSchedulerExtensionAbility' ``` ## WorkSchedulerExtensionAbility.onWorkStart - **系统能力**: SystemCapability.ResourceSchedule.WorkScheduler - **接口**: onWorkStart(workInfo: WorkInfo); - **说明**: 延迟任务调度开始回调。 - **示例**: ``` export default class MyWorkSchedulerExtensionAbility extends WorkSchedulerExtensionAbility { onWorkStart(workInfo) { console.log('MyWorkSchedulerExtensionAbility onWorkStart' + JSON.stringify(workInfo)); } } ``` ## WorkSchedulerExtensionAbility.onWorkStop - **系统能力**: SystemCapability.ResourceSchedule.WorkScheduler - **接口**: onWorkStop(workInfo: WorkInfo); - **说明**: 延迟任务调度结束回调。 - **示例**: ``` export default class MyWorkSchedulerExtensionAbility extends WorkSchedulerExtensionAbility { onWorkStop(workInfo) { console.log('MyWorkSchedulerExtensionAbility onWorkStop' + JSON.stringify(workInfo)); } } ```