JavaScript通过key对map值进行排序
> 我们知道map是无序的，想对map进行排序，就得进行相应的转化。
```
function sortMap(){
var hashmap = {"2":"javascript","1":"java","5":"golang","8":"lua"};
console.log(hashmap);
var keys = new Array();
for(var key in hashmap){
keys.push(key);
}
keys.sort(function(a,b){return b-a});
for(var index in keys){
var key = keys[index];
console.log(hashmap[key]);
}
}
```