#鸿蒙通关秘籍#如何在鸿蒙开发中使用Promise模式实现异步操作？

const promise: Promise<number> = new Promise((resolve: Function, reject: Function) => {
setTimeout(() => {
  const randomNumber: number = Math.random();
  if (randomNumber > 0.5) {
    resolve(randomNumber);
  } else {
    reject(new Error('Random number is too small'));
  }
}, 1000);
})

import { BusinessError } from '@ohos.base';

promise.then((result: number) => {
 console.info(`Random number is ${result}`);
}).catch((error: BusinessError) => {
 console.error(error.message);
});
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