1.notificationManager.cancelAll
支持設備Phone2in1TabletCarWearable
cancelAll(callback: AsyncCallback<void>): void
取消當前應用所有已發布的通知。使用callback異步回調。
系統能力：SystemCapability.Notification.Notification
?

示例：

import { BusinessError } from '@kit.BasicServicesKit';// cancel回調
let cancelAllCallback = (err: BusinessError): void => {if (err) {console.error(`Failed to cancel all notification. Code is ${err.code}, message is ${err.message}`);} else {console.info(`Succeeded in canceling all notification.`);}
}
notificationManager.cancelAll(cancelAllCallback);

2.notificationManager.cancelAll
支持設備Phone2in1TabletCarWearable
cancelAll(): Promise<void>
取消當前應用所有已發布的通知。使用Promise異步回調。
系統能力：SystemCapability.Notification.Notification
?

示例：

import { BusinessError } from '@kit.BasicServicesKit';notificationManager.cancelAll().then(() => {console.info(`Succeeded in canceling all notification.`);
}).catch((err: BusinessError) => {console.error(`Failed to cancel all notification. Code is ${err.code}, message is ${err.message}`);

本文主要參考引用自HarmonyOS官方網站