解决方法 => Promise.allSettled()

我们都知道Promise.all()具有并发执行异步的能力 但是如果其中某个任务但凡有一个出现reject异常错误 所有任务都会挂掉 所以Promise.allSettled()将是最棒的处理并发执行异步的方法

看段代码 => Promise.all走向catch

 const promise1 = () => {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        resolve('promise1')
      }, 3000)
    })
  }

  const promise2 = () => {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        resolve('promise2')
      }, 1000)
    })
  }

  const promise3 = () => {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        reject('error promise3')
      }, 2000)
    })
  }
  //  Promise.all 会走到catch里面
  Promise.all([promise1(), promise2(), promise3()]).then(res => {
    console.log('成功', res);
  }).catch(err => {
    console.log('失败', err);  // 报错 失败 error promise3  错误信息提示promise3导致的
  })

再看Promise.allSettled()的处理

 const promise1 = () => {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        resolve('promise1')
      }, 3000)
    })
  }

  const promise2 = () => {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        resolve('promise2')
      }, 1000)
    })
  }

  const promise3 = () => {
    return new Promise((resolve, reject) => {
      setTimeout(() => {
        reject('error promise3')
      }, 2000)
    })
  }
  Promise.allSettled([promise1(), promise2(), promise3()]).then(res => {
    console.log('成功1', res);
  }).catch(err => {
    console.log('失败1', err);
  })
  //  Promise.allSettled 不管有没有错误，三个的状态都会返回
  // 上面的方法返回 
   成功1 [
       { status: 'fulfilled', value: 'promise1' },
       { status: 'fulfilled', value: 'promise2' },
       { status: 'rejected', reason: 'error promise3' }
      ]