Promise语法
new Promise((resolve, reject) => {
resolve('OK') //成功
resolve('err') //失败
})
Promise.all 包含的promise所有的成功返回成功，一个失败返回失败
const p1 = new Promise((resolve, reject) => {
resolve('OK')
})
const p2 = new Promise((resolve, reject) => {
resolve('OK')
})
const p3 = new Promise((resolve, reject) => {
reject('err')
})
Promise.all([p1, p2, p3]).then(res => {
console.log(res)
})
Promise.any包含的promise一个成功返回成功，所有的失败返回失败
const p1 = new Promise((resolve, reject) => {
resolve('OK')
})
const p2 = new Promise((resolve, reject) => {
resolve('OK')
})
const p3 = new Promise((resolve, reject) => {
reject('err')
})
Promise.any([p1, p2, p3]).then(res => {
console.log(res)
})
Promise.race包含的promise哪一个先返回结果就返回它的状态
const p1 = new Promise((resolve, reject) => {
resolve('OK')
})
const p2 = new Promise((resolve, reject) => {
resolve('OK')
})
const p3 = new Promise((resolve, reject) => {
reject('err')
})
Promise.race([p1, p2, p3]).then(res => {
console.log(res)
})
