computer["home1"] = new Computer(...) // computer.home1
computer["office1"] = new Computer(...) //computer.office1
computer["office2"] = new Computer(...)//computer.office2
这三行分别是Computer的实例。
computer["home1"] = new Computer(...) 时 this 是 computer["home1"]
computer["office1"] = new Computer(...) 时 this 是 computer["office1"]
computer["office2"] = new Computer(...) 时 this 是 computer["office2"]
computer -> {home1:{15...2GHZ},office1:{14,1.4GHZ}...}
这一段代码中代表computer方法本身