kotlin

基础类型

概图

要点

• 常量val和变量var定义

• 字符串模型：$val1

• 自增++(减--)运算符，与java的一致

• 字符串与java类似

// val name: data type = initial value
fun main() {
    //变量定义
    val count: Int = 2
    println(count)
    //output 2
    
    //字符串模型 $+变量名
    println("You have $count unread messages.")
    //output: You have 2 unread messages.
    
    //类型推断
    val count2 = 2
    //数学运算
    val unreadCount = 5
    val readCount = 100
    println("You have ${unreadCount + readCount} total messages in your inbox.")
    //output: You have 105 total messages in your inbox.
    
    //运算示例2
    val totalPhotos = 100
    val delPhotos = 10
    println("$totalPhotos photos")
    println("$delPhotos photos deleted")
    println("${totalPhotos - delPhotos} photos left")
    /**
    * output:
    * 100 photos
    * 10 photos deleted
    * 90 photos left
    **/
}