es6的map是有序吗

letmap=newMap();

map.set免费云主机、域名('JacksonWang','123');
map.set('LEO','456');
map.set('Z-','789');

console.log(map.size);
console.log(map.get('JacksonWang'));
console.log(map.get('LEO'));
console.log(map.has('Z-'));

//输出:3
//123
//456
//true

letmap=newMap();

map.set('JacksonWang','123');
map.set('LEO','456');
map.set('Z-','789');

map.delete('Z-');
console.log(map.size);

console.log(map.clear())

//输出:2
//undefined

letmap=newMap();

map.set('JacksonWang','123');
map.set('LEO','456');
map.set('Z-','789');

console.log(map.keys())//打印所有的键
console.log(map.values())//打印所有的值
console.log(map.entries())//以键值对的方式

/*输出：
[MapIterator]{'JacksonWang','LEO','Z-'}
[MapIterator]{'123','456','789'}
[MapEntries]{
['JacksonWang','123'],
['LEO','456'],
['Z-','789']
}*/

letmap=newMap();

map.set('JacksonWang','123');
map.set('LEO','456');
map.set('Z-','789');

for(const[key,value]ofmap.entries()){
console.log(`${key}:${value}`);
}
/*输出:
JacksonWang:123
LEO:456
Z-:789
*/

letmap1=newMap([
[1,'One'],
[2,'Two'],
[3,'Three']
])

console.log([...map1.keys()]);
console.log(...map1.entries())
console.log([...map1.entries()]);

/*输出:
[1,2,3]
[1,'One'][2,'Two'][3,'Three']
[[1,'One'],[2,'Two'],[3,'Three']]
*/

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WeskMap测试

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WeskMap测试

functionPerson(name){
this._name=name;
}

Person.prototype.getName=function(){
returnthis._name;
}
//但这是，创建一个Person对象的时候，我们可以直接访问name
letp=newPerson('张三');
console.log(p._name)

//输出：张三

letPerson=(function(){
letprivateData=newWeakMap();
functionPerson(yourname){
privateData.set(this,{_name:yourname})//this当前这个键的对象
}
Person.prototype.getName=function(){
returnprivateData.get(this)._name;//
}
returnPerson;
})();//定义好了函数就开始执行

letp=newPerson('jack');
console.log(p._name)//因为name的私有型，所以在外不可访问
console.log(p.getName())

/*输出:
undefined
jack
*/