function Dictionary(){ // 定義字典存儲鍵值對 this.dirctionary = {}; // 添加一個存儲鍵值對 Dictionary.prototype.add = function(key,value) { this.dirctionary[key] = value; } // 刪除一個存儲鍵值對 Dictionary.prototype.delete =function(key) { if(this.dirctionary.hasOwnProperty(key)) { delete this.dirctionary[key]; } } // 根據key返回一個item Dictionary.prototype.get = function(key) { return this.dirctionary.hasOwnProperty(key)? this.dirctionary[key] : undefined; } // 打印字典 Dictionary.prototype.toString = function(){ for (const iterator in this.dirctionary) { console.log(this.dirctionary[iterator]); } } } var d = new Dictionary(); d.add("1","123") d.add("1","125") d.add("2",[1,2,3,4,5]); d.toString(); d.delete("1"); d.toString(); console.log(d.get("2"))