承诺承诺

Question

我有检查数组中值的函数

    const arr = [10,20,30];
    const check = (needle) => {
            return new Promise((resolve, reject) => {
                arr.includes(needle) ? resolve('err') : reject('err');
            })
        };

在自定义案例

中的工作原理如下

checkPermissionByRole(100)
            .then(val => console.log(val))
            .catch( err => console.log(err)) // gives 'err' as expected 

但我想做点像

const arr = [10,20,30];
const second = [40,50,60];

const check = (needle) => {
                return new Promise((resolve, reject) => {
                    arr.includes(needle) ? resolve('err') : // call check again but with another array to check in
                })
            };

如果一个promise给了我一个被拒绝的值，请使用相同的函数（和相同的参数）再次检查它，它给了我一个承诺，但是list / array（arr one）应该是second而不是arr。我以为我可以用携带的结构来做，如果没有，给我一些思考的面包

Answer 1

如果要检查两个数组中是否包含needle，您可以这样做：

(arr.includes(needle) || second.includes(needle)) ? resolve('err') : reject('err');

Answer 2

试试这个：

const arr = [10,20,30];
const second = [40,50,60];

const check = (needle) => {
  return new Promise((resolve, reject) => {    
    arr.includes(needle) && resolve('err1') ||
    second.includes(needle) && resolve('err2') || reject('err');
  })
};