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Head First Kotlin程序设计
book

Head First Kotlin程序设计

by Dawn Griffiths, David Griffiths
August 2020
Intermediate to advanced
483 pages
11h 24m
Chinese
China Machine Press
Content preview from Head First Kotlin程序设计
你现在的位置 4 41
basic types and variables
基本类型和变量
var Int
Long
5
引用
x
引用
z
Int
5
var Long
var x = 5
这行代码创建了一个Int类型的变量x以及一个Int类型值为
5
的对象。x保存了该对象
的引用。
1
var Int
Int
5
引用
x
数值类型转换背后发生了什么
var z: Long = x.toLong()
这行代码创建了一个新的Long变量zx对象的toLong()函数被调用并且创建了一个值
5
Long对象。该Long对象的引用被存储在z中。
2
toLong()
该方法可以较好地应用于从存储小数据的类型转换为能存储较大
数据的类型。那么,如果该数值超出了新对象所能存储的范围该
怎么办呢?
toLong()
函数创建了一个
L
ong
对象
该对象和
Int
对象有相同的值
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Publisher Resources

ISBN: 9787111662358