具体代码如下：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<script>
function getName(item){
return new Promise((resolve, reject)=>{
let sino = parseInt(Math.random() * 5000)
console.log(sino);
setTimeout(()=>{
resolve(item*2)
},sino)
})
}
async function getAllHistory() {
let allHistory = []
let list = [1,2,3,4,5];
list.forEach((item)=>{
allHistory.push((async(item)=>{
return await getName(item)
})(item))
})
return await Promise.all(allHistory);
}
getAllHistory().then((res)=>{
console.log(res);
})
</script>
</body>
</html>
原文：https://www.cnblogs.com/xiaozhumaopao/p/14623946.html