基础

1 类的创建

类的创建，比如指定属性的默认值才行，不然编译器会报错

class Address {
    var name: String = ……
    var street: String = ……
    var city: String = ……
    var state: String? = ……
    var zip: String = ……
}

如果要写Get或者Set的方法，可以按以下的方式来写

var name: String = ""
    var street: String = ""
    var city: String = ""
    var state: String? = ""
    var zip: String = ""
    var isDown : Boolean
        get() = name.equals("11")
        set(value) {name = when(value){true -> ""
                                       false -> ""}}