JS promise解决异步问题过程详解

function onSubmitPost (data) {
	fetch('https://test.post.com', {
		method: 'POST',
		body: JSON.stringify(data)
	})
}
function getAddress (func) {
	const address = '北京市朝阳区牛！'
	func(address)
}
const getUserInfo = (func) => {
	const userInfo = {name: '测试', age: '20'}
	func(userInfo)
}
function onSubmit () {
	getAddress((address)=>{
		const addr = address
		getUserInfo((userInfo)=>{
			const user = userInfo
			onSubmitPost({addr,...userInfo})
		})
	})
}
onSubmit()

function getInfo (key) {
	return new Promise((resolve, reject)=>{
		const datas = {
			address: '北京市朝阳区牛！', 
			user: {
				name: '测试', 
				age: '20'
			}
		}
		if (datas[key]) {
			resolve(datas[key])
		} else {
			reject('没有')
		}
	})
}
getInfo('address').then((res)=>{
	const address = res
	return getInfo('user')
}).then((res)=>{
	const user = res
	onSubmitPost({address, ...user})
})

async function sumbit () {
	const address = await getInfo('address')
	const user= await getInfo('user')
	onSubmitPost({address, ...user})
}