kotlin 的基本数据类型

 

Kotlin 的基本数值类型包括 Byte、Short、Int、Long、Float、Double 等。不同于Java的是，字符不属于数值类型，是一个独立的数据类型。

类型	位宽度
Double	64
Float	32
Long	64
Int	32
Short	16
Byte	8

 

/**
 * Created by jingwen.
 */
fun main(args:Array<String>){

    //整型
    var age:Int = 12;
    var direct:Byte = 1;
    var band:Short = 1;
    var salary:Long = 44433333;

    //浮点型
    var zhuSalary:Float = 5223.4f;
    var famlySalary:Double = 112424422443.0

    //boolean
    var isBoy:Boolean = true


    var  char:Char = 'a';
    var  name:String = "hello jingwen"

    println("age ="+age)
    println("direct ="+direct)
    println("band ="+band)
    println("salary ="+salary)

    println("isBoy ="+isBoy)

    println("zhuSalary ="+zhuSalary)
    println("famlySalary ="+famlySalary)

    println("char ="+char)
    println("name ="+name)



    //最大值和最小值
    var  intMax:Int = Int.MAX_VALUE;
    println("int max:")
    println(intMax)
    println(Math.pow(2.0,31.0)-1)

    println("int min")
    var intMin:Int = Int.MIN_VALUE;
    println(intMin)


    println(-Math.pow(2.0,31.0))


    println("float max")
    var floatMax = Float.MAX_VALUE
    println(floatMax)

    println("float min")
    var floatMin = -Float.MAX_VALUE
    println(floatMin)
    println(Float.MIN_VALUE)

    //非数值,kotlin独有的
    println(0.0f/0.0f)


    //类型转换必须是显示转换
    var a:Int = 12;
    var b:Byte = a.toByte();


    var  c:Long = b.toLong();

    //字符串模板
    var num1:Int = 1
    var num2:Int = 2
    //java普通方式
    println(""+num1 +"+"+num2+"="+(num1+num2))
    //kotlin 模板
    println("$num1+$num2=${num1+num2}")

    //"""

    var string:String = """
    jingwen
    zhu
    \t
    \n
    cc
    """

    println(string)
    println("字符的个数 ${string.length}")

    //字符串的比较
    var  s1:String = String(charArrayOf('a','b','c','d'))
    var  s2:String = "abcd"
    println(s1==s2)//public open operator fun equals(other: Any?): Boolean
    println(s1===s2)//判断是否同一个对象





}

运行结果:

age =12
direct =1
band =1
salary =44433333
isBoy =true
zhuSalary =5223.4
famlySalary =1.12424422443E11
char =a
name =hello jingwen
int max:
2147483647
2.147483647E9
int min
-2147483648
-2.147483648E9
float max
3.4028235E38
float min
-3.4028235E38
1.4E-45
NaN
1+2=3
1+2=3

    jingwen
    zhu
    \t
    \n
    cc
    
字符的个数 46
true
false