1.定義一個類
// 第一種主構(gòu)造函數(shù)
class Friend constructor(val name:String, val age:Int){}
// 2
class Friend constructor(name:String, age:Int){
val name = name
val age = age
}
// constructor關(guān)鍵字可以省略,如果主構(gòu)造函數(shù)有注解或者修飾符就不能省略
class Friend(val name:String, val age:Int){}
// 主構(gòu)造函數(shù)里面是不能有代碼的，但是有一個init代碼塊可以在里面寫構(gòu)造之后的邏輯代碼
class Friend(name:String, age:Int){
init{
print("Hello,Friend${name}")
}
val name = name
val age = age
}
// 次構(gòu)造函數(shù)
class Friend{
constructor(name:String, age:Int){
this.name = name
this.age = age
}
val name:String
val age:Int
}
// 主構(gòu)造函數(shù) 加 次構(gòu)造函數(shù)并齐，次構(gòu)造還是要轉(zhuǎn)到主構(gòu)造
class Friend(name:String, age:Int){
constructor(name:String, age:Int, height:Int):this(name, age){
this.height = height
}
val name:String = name
val age:Int = age
val height:Int? = null
}
2.私有化構(gòu)造方法
class Friend private constructor(){}
3.函數(shù)作為屬性賦值
class numComputer(val num1:Int, val num2:Int, var operator: (int, int)->int){
fun operation():Int{
return operator(num1, num2)
}
}
val nc = numComputer(1,2){x, y -> x+y}
nc.operation()
nc.operator = {x, y-> x*y}
nc.operation()
4.屬性的get() set() 方法
var 是可變屬性漏麦，具有g(shù)et() 和set()方法
val是常量， 所以沒有set() 方法
calss Person(age: Int){
var age = age
set(value){
// 給當前的這個屬性賦值
field = value
isAudlt = if(age>18) true else false
}
var isAudlt:Boolean= false
private set
var addAge:int = 0
set(value){
age += value
}
}
