数据类型 swift

1整形

Int,Int8,Int16,Int32,Int64

UInt,UInt8,UInt16,UInt32,UInt64

其中Int,UInt始终和当前平台的原生字长相同(32位机，64位机)

查看属性

UInt8.min

UInt8.max

初始化

var sampleInteger:Int

var tmpInteger = 12

var tmpInteger = Int.init(12)

let binaryInt:Int = 0b10001

let octalInt:Int = 0o21

let hexadecimalInt:Int = 0x11

let bignum_a = 1000000

let bignum_b = 1_000_000

let bignum_c = 1_0000_0000

2浮点型

Float

Double(默认)

let float_a = 0.012

let float_b = 1.2e-2

3布尔

Bool

4字符串

String

字符串插值

println("The current value of friendlyWelcome is (friendlyWelcome)")

// 输出 "The current value of friendlyWelcome is Bonjour!

计算长度countElements()

比较字符串可以用 ==

hasPrefix() hasSuffix()判断是否有前缀和后缀

uppercaseString() lowercaseString()

isEmpty属性

capitalizedString(每个单词首字母大写，需要导入Foundation库)

stringByTrimmingCharactersInSet() (trim)

componentSeperatedByString() (split)

//join

var str4 = "-"

str4.join(["1","2","4"])

rangeOfString() 匹配查找

substringToIndex()

substringFromIndex()

substringWithRange()

insertIndex()

insert()

removeAtIndex()

removeRange()

replaceEndIndex()

5字符

Character

6可选

Optional

7元组

类型别名

typealias ShortInteger = Int8