3-6 实现一个 promise.all 方法
function jmPromiseAll(list) {
const result = [];
let count = 0;
return new Promise((reslove, reject) => {
list.forEach(promise => {
promise.then((res) => {
result.push(res)
count++;
if(count >= list.length) {
reslove(result)
}
}, reject)
})
})
}
const p1 = new Promise((reslove, reject) => {
setTimeout(()=> {
reslove(1000)
},1000)
})
const p2 = new Promise((reslove, reject) => {
setTimeout(()=> {
reject(2000)
},2000)
})
jmPromiseAll([p1,p2]).then(res => {
console.log(res)
})