Map映射, 存储多个键值对数据, 类似对象。
Map的用法 var map=new Map() -----创建map
map.set(key,value)-----存储值
map.get(key) ----- 获取值
for(var [key,value] of map)------遍历
map.delete(key)------ 删除值
map.clear() ------清空
<body>
<script>
var map=new Map();//创建map,且分别设置它的key和value值
map.set("name","shannon");
map.set("age",22);
map.set("hobby","code");
var hobby=map.get("hobby");//获取到上面设置的“hobby”值
console.log("Shannon's hobby is about "+hobby);
//同理
var name=map.get("name");//获取到上面设置的“hobby”值
console.log("My name is "+name);
// /My name is shannon
//Shannon's hobby is about code.
for(var [key,value] of map){//将map的key和value值传入且打印
console.log("key= "+key+", value= "+value);
}
// key= name, value= shannon
// key= age, value= 22
// key= hobby, value= code
</script>
</body>