動態改變json key值 和value值

var obj = {
						user_id: "that.user_id",
						auth_id: "that.auth_id",
						token: "that.token",
						id: "that.bigData.id",
						v_type: "that.bigData.v_type",
					}
                    //新增key，動態改值
					var key = "demo";
					obj[key] = "text";
                    //修改key的value值
					obj["id"] = "22222222";
					console.log(JSON.stringify(obj))