Swift Introduction

1: var x: Double = 4.3
2: var y: Double = 3.4
3: var z: Double {
4:     return x*y
5: }
6: print(z)
7: x = 10
8: y = 10
9: print(z) //自動重新計算z值

1: var body: som View {
2:     return Text("Hello world")
3: }

1: print(1 + 2)       // 等於 3
2: print(5 - 3)       // 等於 2
3: print(2 * 3)       // 等於 6
4: print(10.0 / 2.5)  // 等於 4.0
5: print(10 / 3)      // 等於 1
6: print(10 & 3)      // 等於 1

"exports both"body

1: "hello, " + "world"  // 等於 "hello, world"

1: temperatureInFahrenheit = 40
2: if temperatureInFahrenheit <= 32 {
3:     print("It's very cold. Consider wearing a scarf.")
4: } else {
5:     print("It's not that cold. Wear a t-shirt.")
6: }

1: temperatureInFahrenheit = 90
2: if temperatureInFahrenheit <= 32 {
3:     print("It's very cold. Consider wearing a scarf.")
4: } else if temperatureInFahrenheit >= 86 {
5:     print("It's really warm. Don't forget to wear sunscreen.")
6: } else {
7:     print("It's not that cold. Wear a t-shirt.")
8: }

1: switch some value to consider {
2: case value 1:
3:     respond to value 1
4: case value 2,
5:      value 3:
6:     respond to value 2 or 3
7: default:
8:     otherwise, do something else
9: }

1: let someCharacter: Character = "z"
2: switch someCharacter {
3: case "a":
4:     print("The first letter of the alphabet")
5: case "z":
6:     print("The last letter of the alphabet")
7: default:
8:     print("Some other character")
9: }

 1: // 把分數轉成等第
 2: // A(90-100), B(80-90), C(70-80), D(60-70), E(60-)
 3: import Foundation
 4: 
 5: let str = readLine()    //從鍵盤讀入一字串, 存到str中
 6: let choice = Int(str!)   //把str轉成整數，存入score
 7: 
 8: switch choice! {
 9: case 90..<101:
10:     print("A")
11: case 80..<90:
12:     print("B")
13: case 70..<80:
14:     print("C")
15: default:
16:     print("E")
17: }
18: 

1: for counter in lower...upper{
2:     your codes
3: }

1: for index in 1...5 {
2:     print("\(index) times 5 is \(index * 5)")
3: }

1: let base = 3
2: let power = 10
3: var answer = 1
4: for _ in 1...power {
5:     answer *= base
6: }
7: print("\(base) to the power of \(power) is \(answer)")

1: var EnglishScores = [Int]()
2: print(EnglishScores)
3: // OR
4: var NameArray = [String]()

1: var shoppingList: [String] = ["Eggs", "Milk"]
2: // shoppingList 已經被建構並且擁有兩個初始項。

 1: var shoppingList: [String]  = ["Eggs", "Milk"]
 2: print(shoppingList.count)
 3: print(shoppingList.isEmpty)
 4: shoppingList += ["Bird"]  // Not += "Bird"
 5: shoppingList.append("Fish")
 6: print(shoppingList)
 7: print(shoppingList[0])
 8: shoppingList += ["Beer"]
 9: print(shoppingList)
10: shoppingList.remove(at: 1)
11: print(shoppingList)

1: var shoppingList: [String]  = ["Eggs", "Milk", "Beer"]
2: for index in 0...2 {
3:     print(shoppingList[index])
4: }
5: for item in shoppingList {
6:     print(item)
7: }

1: let nums1 = [Int](repeating: 0, count: 10)
2: let str1 = [String](repeating: "TNFSH", count: 5)
3: print(nums1)
4: print(str1)
5: 
6: let nums2 = [[Int]](repeating: [Int](repeating: 6, count: 3), count: 2)
7: print(nums2)

1: let nums = [2, 3, 4]
2: let mapped = nums.map { Array(repeating: $0, count: $0) }
3: print(mapped)
4: 
5: let flatMapped = mapped.flatMap{$0}
6: print(flatMapped)
7: 

1: let possibleNums = ["1", "2", "three", "///4///", "5"]
2: let mapped = possibleNums.map { str in Int(str) }
3: print(mapped)
4: 
5: let comMapped = possibleNums.compactMap { str in Int(str) }
6: print(comMapped)

1: let book = ["X的悲劇", "地獄藍調","東方列車謀殺案","八百萬種死法","血字研究"]

1: let book = ["X的悲劇", "地獄藍調","東方列車謀殺案","八百萬種死法","血字研究"]
2: let author = ["艾勒里．昆恩", "李查德", "阿嘉莎‧克莉絲蒂","勞倫斯.卜洛克","柯南道爾"]

1: struct Book {
2:     var title: String
3:     var author: String
4: }

 1: struct Book {
 2:     var title: String
 3:     var author: String
 4: }
 5: var books = [
 6:     Book(title:"X的悲劇", author: "艾勒里．昆恩"),
 7:     Book(title:"地獄藍調", author: "李查德"),
 8:     Book(title:"東方列車謀殺案", author: "阿嘉莎‧克莉絲蒂"),
 9:     Book(title:"八百萬種死法", author: "勞倫斯.卜洛克"),
10:     Book(title:"血字研究", author: "柯南道爾")
11: ]
12: // 存取陣列中struct的方式
13: print(books[1].title)
14: print(books[1].author)

1: var letrers = Set<Character>()

 1: var letters = Set<Character>()
 2: print(letters.count)
 3: letters.insert("a")
 4: print(letters.isEmpty)
 5: letters.insert("b")
 6: letters.insert("c")
 7: letters.insert("d")
 8: letters.remove("c")
 9: for item in letters {
10:     print("\(item)")
11: }

1: let oddDigits: Set = [1, 3, 5, 7, 9]
2: let evenDigits: Set = [0, 2, 4, 6, 8]
3: let primeNumbers: Set = [2, 3, 5, 7]
4: 
5: print(oddDigits.union(evenDigits))
6: print(oddDigits.union(evenDigits).sorted())
7: print(oddDigits.intersection(evenDigits).sorted())
8: print(oddDigits.subtracting(primeNumbers).sorted())
9: print(oddDigits.symmetricDifference(primeNumbers).sorted())

1: var namesOfIntegers = [Int: String]()
2: // namesOfIntegers is an empty [Int: String] dictionary
3: namesOfIntegers[16] = "Sixteen"
4: print(namesOfIntegers)

1: [key 1: value 1, key 2: value 2, key 3: value 3]

1: var autherOfWriting: [String: String] = ["老人與海": "海明威", "異鄉人": "卡謬", "百年孤寂": "馬奎斯", "浪淘沙": "東方白"]
2: print(autherOfWriting)
3: print("一共有\(autherOfWriting.count)本書")
4: print(autherOfWriting.isEmpty)
5: autherOfWriting["鼠疫"] = "卡謬"
6: for (writing, author) in autherOfWriting {
7:     print("\(writing)的作者為\(author)")
8: }

1: func name(arg1 param1: DataTyp, arg2 param2: DataType) -> returnValue DataType {
2:      your code here
3:      return returnValue
4: }

"exports both"body

 1: import Foundation
 2: 
 3: class ClosureTesting {
 4:     let queue = DispatchQueue(label: "concurrentQueue", attributes: .concurrent)
 5:     func getUser(completion: (String)->Void) {
 6:         queue.async {
 7:             // let sepnd some time to fetch the data
 8:             Thread.sleep(forTimeInterval: Double.random(in: 0...2))
 9:             completion("TNFSH")
10:         }
11:     }
12:     func execute() {
13:         getUser { user in
14:             print(user)
15:         }
16:     }
17: }
18: let test = ClosureTesting()
19: test.execute()

 1: import Foundation
 2: 
 3: class ClosureTesting {
 4:     let queue = DispatchQueue(label: "concurrentQueue", attributes: .concurrent)
 5:     func getUser(completion: @escaping (String)->Void) {
 6:         queue.async {
 7:             // let sepnd some time to fetch the data
 8:             Thread.sleep(forTimeInterval: Double.random(in: 0...2))
 9:             completion("TNFSH")
10:         }
11:     }
12:     func execute() {
13:         getUser { user in
14:             print(user)
15:         }
16:     }
17: }
18: let test = ClosureTesting()
19: test.execute()
20: 

 1: func sortArray(array:[Int], handler: (([Int])->Void)) {
 2:     // step 2
 3:     var sortedArray: [Int] = []
 4:     sortedArray = array.sorted();
 5:     // step 3
 6:     handler(sortedArray)
 7: }
 8: func doSomething() {
 9:     // setp 1
10:     sortArray(array: [50,333,434,2,8,3,54,73,99,83,13]) {(result) in
11:         // step 4
12:         print("Sorted Array: \(result)")
13:     }
14: }
15: doSomething()

 1: struct Resolution {
 2:     var width = 0
 3:     var height = 0
 4: }
 5: class VideoMode {
 6:     var resolution = Resolution()
 7:     var interlaced = false
 8:     var frameRate = 0.0
 9:     var name: String?
10: }
11: 

1: struct DiceGme {
2:     init(numberOfDices: Int){
3:         // create a dice with that many dices
4:     }
5: }

1: let someResolution = Resolution()
2: let someVideoMode = VideoMode()

1: print("The width of someResolution is \(someResolution.width)")
2: // Prints "The width of someResolution is 0"
3: print("The width of someVideoMode is \(someVideoMode.resolution.width)")
4: // Prints "The width of someVideoMode is 0"

1: someVideoMode.resolution.width = 1280
2: print("The width of someVideoMode is now \(someVideoMode.resolution.width)")
3: // Prints "The width of someVideoMode is now 1280"

 1: struct Person {
 2:     let firstName: String
 3:     let lastName: String
 4: }
 5: 
 6: struct Employee {
 7:     let identity: Person
 8:     var jobTitle: String
 9:     var salary: Double
10: }
11: 
12: let me = Person(firstName: "Letranger", lastName: "Yen")
13: var letranger = Employee(identity: me, jobTitle: "CEO", salary: 3000)
14: 
15: print(me.firstName)
16: print(letranger.identity)
17: print(letranger.jobTitle)

 1: struct Person {
 2:     let firstName: String
 3:     let lastName: String
 4: }
 5: 
 6: struct Employee {
 7:     let identity: Person
 8:     var jobTitle: String
 9:     var salary: Double
10: 
11:     var tax: Double {
12:         return salary * 0.05
13:     }
14: }
15: 
16: let me = Person(firstName: "Letranger", lastName: "Yen")
17: var letranger = Employee(identity: me, jobTitle: "CEO", salary: 3000)
18: 
19: print(letranger.tax)

 1: struct Person {
 2:     let firstName: String
 3:     let lastName: String
 4: }
 5: struct Employee {
 6:   static var location = "高雄"
 7:   let identity: Person
 8:   var jobTitle: String
 9:   var salary: Double
10: }
11: print(Employee.location)

 1: struct Person {
 2:     let firstName: String
 3:     let lastName: String
 4: }
 5: 
 6: struct Employee {
 7:     let identity: Person
 8:     static var location = "高雄"
 9:     var jobTitle: String
10:     var salary: Double {
11:         didSet {
12:             if salary >= oldValue * 2 {
13:                 Employee.location = "國外"
14:             }
15:         }
16:     }
17: 
18:     var tax: Double {
19:         return salary * 0.05
20:     }
21: }
22: 
23: let me = Person(firstName: "Letranger", lastName: "Yen")
24: var letranger = Employee(identity: me, jobTitle: "CEO", salary: 3000)
25: 
26: print(letranger.tax)
27: print(Employee.location)
28: letranger.salary = 10000
29: print(Employee.location)

 1: struct Birthday {
 2:   var day: Int = 12
 3:   var month: Int = 12
 4:   var year: Double = 1999
 5: 
 6:   func myBirthday() {
 7:   print("I've born in \(year).\(month).\(day)")
 8:   }
 9: }
10: 
11: struct Person {
12:   var firstName: String = "Abboskhon"
13:   var lastName: String = "Shukurullaev"
14:   var phoneNumber: String = 123456
15:   var emailAddress: String = "abbsh24@gmail.com"
16: 
17:   func myInfo() {
18:   print("My name is \(firstName) \(secondName). My phone number is \(phoneNumber) and email address is \(emailAddress)")
19:   }
20: }

 1: struct Counter {
 2:   var count: Int = 0
 3: 
 4:   mutating func increment() {
 5:     count += 1
 6:   }
 7:   mutating func increment(by amount: Int) {
 8:     count += amount
 9:   }
10:   mutating func reset() {
11:     count = 0
12:   }
13: }
14: var counter = Counter()   //default is 0
15: counter.increment()       //becomes 1
16: counter.increment(by: 9)  //becomes 10
17: counter.reset()           //reset to 0

 1: class Animals {
 2:     func animals() {
 3:         print("Animals are mainly of 3 types: Land Animals, Sea animals, Air Animals")
 4:     }
 5: }
 6: 
 7: class LandAnimals: Animals {
 8:     override func animals() {
 9:         print("Land animals are cats, sheeps, horses.")
10:     }
11: }
12: 
13: class Cat: LandAnimals {
14:     override func animals() {
15:         print("I am a cat and I am a land animal.")
16:     }
17: }

 1: //學生1資料
 2: var st1-no = "S01"
 3: var st1-name = "James"
 4: var st1-english = 93
 5: var st1-math = 90
 6: //學生2資料
 7: var st2-no = "S02"
 8: var st2-name = "Vanessa"
 9: var st2-english = 90
10: var st2-math = 99

 1: struct Student {
 2:     var no: String?
 3:     var name: String
 4:     var english = 0.0
 5:     var math = 0.0
 6: }
 7: 
 8: let st1 = Studetn(no: "S01", name: "James", english: 93, math: 92)
 9: let st2 = Studetn()
10: st2.no = "S02"
11: st2.name = "Vanessa"
12: st2.english = 90
13: st2.math =  99

1: enum Status: String {
2:   case pending = "审核中"
3:   case approved = "审核通过"
4:   case failed = "审核未通过"
5: }
6: print(Status.pending.rawValue) // 审核中

 1: enum Status: String {
 2:   case pending
 3:   case approved
 4:   case failed(msg: String)
 5: }
 6: 
 7: func review(_ name: String) -> Status {
 8:   if name.count > 10 {
 9:     return .failed(msg: "名字太长了")
10:   }
11:   return .pending
12: }
13: 
14: print(review("dsafs")) // pending
15: review("dsafsdfsdfsd") // failed(msg: "名字太长了")