IOS 学习1

swift

变量 Use let to make a constant and var to make a variable

var MyVar = 1
MyVar = 2
let MyConstant = 2
let num: Double = 3
let appleSummary = "I have \(num) apples."

let quotation = """
I said "I have \(apples) apples."
"""

dictionaries and array

var shopList = ["apple", "banana"]
var shopDict = ["apple": 5, "banana": 3]

shopList.append("pear")

控制语句

let scores = [1, 2, 3]
var teamScore
for score in scores {
    if score > 2 {
        teamScore += score
    }
}

let vegetable = "red pepper"
switch vegetable {
    case "celery":
        print("celery")
    case "apple":
        print("apple")
    default: 
        print("ahhah default")
}


function 
function greet (person: String, day: String) -> String {
    return "hello \(person), today is \(day)"
}

greet(person: "Tom", day: "Tuesday")

类

class NameShap {
    var numberOfSizes: Int = 0
    var name:String
    
    init(name: String) {
        self.name = name
    }
    
    func simpleDescription() -> String {
        return "A shape is \(name)"
    }
}

class Square:NameShap {
    var sideLength: Double
    init(sideLength: Int, name: String) {
        self.sideLength = sideLength
        super.init(name:name)
        numberOfSizes = 4
    }
    
    override func simpleDescription() -> String {
        return "A square is \(name)"
    }
}

待续...