Swift4 初步认识
基于版本号:4.1.2
在一行中声明多个常量或变量,用逗号隔开
var a =3,b=4,c=5;
var Who:String //声明一个String的变量Who
Who = "imaginecode"
println(Who)
可以使用汉字、表情命名等任意字符。但不能包含数学符号、箭头、连线与制表符,不能以数字开头
var apples = 10
var oranges = 4
println("I have \(apples + oranges) fruits") //占位符表示方式
let a: UInt8 =10
let b: Uint6 = 100
print("\(UInt16(a)+b)")
typealias AudioSample = UInt16
var maxValue = AudioSample.min
(true,"imagine","男")
(404,"Not Found")
特点:
let registInfo = (isTrue:true,nickname:"imagine",gender:"男")
let (isTrue,nickname,gender) = registInfo
registInfo.isTrue // true
let loginResult = (true,"imagine")
let (isLogin,_) = loginResult
if isLogin {
print("success")
}
var imOptionalVariable:Int? //nil
imOptionalVariable = 12 //12