入门 Swift 第一章

折腾 › Swift
, ,

变量！哦，还有常量

作为 JavaScript 开发者可能需要习惯一下 var 只为了变量，let 只为了常量这个设定

声明数据类型

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var text: String = "Hello, Apple"
let number: Int = 12

不声明

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var text = "Hello, Apple"
let number = 12

来了，函数

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func uncle() {
    print("叔叔我啊，真的是要爱死温迪了")
}

uncle()
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func loveIt(name: String) {
    print("叔叔我啊，真的是要爱死\(name)了")
}

loveIt(name: "空")
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func loveIt(_ name: String) {
    print("叔叔我啊，真的是要爱死\(name)了")
}

loveIt("空")
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func loveIt(name: String) -> String {
    return "叔叔我啊，真的是要爱死\(name)了！"
}

print(loveIt(name: "派蒙"))
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func superLoveIt(c1: String, c2: String, c3: String) -> String {
    return "叔叔我啊，真的不仅仅要爱\(c1)了，还要爱\(c2)和\(c3)"
}

print(superLoveIt(c1: "温迪", c2: "空", c3: "派蒙"))

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func loveIt(c1: String, c2: String, c3: String) -> (String, String, String) {
    return (c1, c2, c3)
}

let result = loveIt(c1: "温迪", c2: "空", c3: "派蒙")

print(result.0, result.1, result.2)

控制流来了

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let number = 20

if number == 20 {
    print("Ya")
} else {
    print("NOOO")
}

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let number = 30

if number == 20 {
    print("20")
} else if number == 30 {
    print("30")
} else {
    print("I don't know bro...")
}

循环，但愿不要死循环

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for i in "What the..." {
    print(i)
}
``

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for i in "What the..." where i != "." {
    print(i)
}