第一个Swift程序
print("Hello, world!")
//默认情况下printf()函数输出后会自动换行，如果不希望换行，可以通过指定terminator参数设定自己的是否换行
print("Hello, world!",terminator: "")
变量和常量
let apples = 3
let oranges = 5
let appleSummary = "I have \(apples) apples."//转译字符用法
let fruitSummary = "I have \(apples + oranges) pieces of fruit."
元组
用一个变量或一个常量保存多项信息
let stu: (id: Int, name: String,gender: Bool,age: Int) = (1001,"王大锤",true,23
)
let (_,j, _, k) = stu //下划线表示不要()省略和忽略元组的第一项和第三项
//用元组交换两个变量的值
var x = 5 , y = 10
(x,y) = (y,x)
运算符
// 算数运算符 + - * / %
//关系运算符 == != > >= < <=
//短路运算符 && ||
字符串的连接
var string1 = "hello"
var string2 = "world"
string1 = string1 + " " + string2
三元条件运算符
//let a = 5 , b = 10
//let c = a < b ? a : b
分支结构
游戏举例说明switch case
func name(a:Int)->String{
var msg: String
switch a{
case 1:
msg="石头"
case 2:
msg="剪刀"
case 3:
msg="布"
default:
msg="输入错误"
}
return msg
}
func compare(a:Int,b:Int)->(String,Int,Int){
var msg1: String
var humanWin: Int = 0
var win = 0
if a==b{
msg1="平局"
win = 0
humanWin = 0
}
else if a==1&&b==2 || a==2&&b==3 || a==3&&b==1{
msg1 = "你赢了"
win = 0
humanWin = 1
}
else{
msg1 = "电脑赢了"
win = 1
humanWin = 0
}
return (msg1,humanWin,win)
}
if else 说明
//计算某年的某个月有多少天
//
print("请输入年份：",terminator: " ")
let year = inputInt()
print("请输入月份",terminator: " ")
let month = inputInt()
let day: Int
if year > 0 && month>=1 && month<=12{
if month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12 {
day = 31
}
else if month != 2{
day = 30
}
// else if year % 4 == 0 && year % 100 != 0 || year % 400 == 0 {
// day = 29
// }
// else {
// day = 28
// }
else {day = year % 4 == 0 && year % 100 != 0 || year % 400 == 0 ? 29 : 28}
print("day=\(day)")
}
else{
print("输入错误")
}
循环结构
while 循环--有可能一次都不执行
var i = 0
while i < 10 {
print("\(i)+\"\"Hello, World!")
i += 1
}
repeat while 循环自少要执行一次循环体内容
var i = 1
repeat {
print("\(i).hello,world")
i += 1
}while i <= 10
for 循环
for _ in 1..<10{//_ 下划线表示实参可以省略
print("hello,world")
}
for i in 1...10{
print("\(i).hello,world")
}
数组
//1.创建一个空数组
var array1 = [String]()
var array2:[Int] = []
var array3 = ["hello","world"]
var array4 = [Int](count: 100, repeatedValue: 1)
//修改元素
array3[1...1]=["www"]
print(array3)
//2.向数组中添加元素
array1.append("strawberry")//append追加 insert 插入
array1.append("pear")
array1 += ["pear"]
array1.insert("waxberry", atIndex: 0)
array1.insert("watermelon", atIndex: 2)
array1.insert("lemon", atIndex: array1.count)
print(array1)
//3.从数组中删除元素全是 .remove(xxxx)
array1.removeAll() //元素全部删除完，并回收空间
print(array1)
array1.removeAll(keepCapacity: true)//true只删除元素不会删除空间
array1.removeAtIndex(3)//
array1.removeFirst(100) //删除前100个元素
array1.removeRange(<#T##subRange: Range<Int>##Range<Int>#>)//删除的范围
//4.数组的复制
var array1 = ["hello","world"]
var array2 = array1
array2[0] = "aaaaaa"
//第二种写法
var array3 = array1[1..<array3.count]
//5.数组的元素合并成新数组(数组的+运算)
var array1
var array2
var array3 = array1 + array2
//6.获取数组元素的个数
var array1 = ["hello","world"]
print(array1.count)
//7.对数组中的元素进行遍历
for index in 0..<array3.count{
//[]是对数组进行的下表运算（取出指定位置的元素）
print(array3[index])
if index == 1{
array3[index] = "hhh"
}
}
print(array3)
//只读循环，在循环中不能修改数组中的元素
for str in array3{
print(str)
}
小游戏总结
分支加循环的应用：
猜值游戏
var thyAnswer: Int
var counter = 0
let answer = Int(arc4random_uniform(100)) + 1
repeat {
counter += 1
print("请输入你猜的数字:",terminator:"")
thyAnswer = inputInt()
if thyAnswer > answer{
print("小一点")
}
else if thyAnswer < answer{
print("大一点")
}
else {
print("恭喜你，猜对了，你总共猜了\(counter)次")
}
}while thyAnswer != answer
if counter > 7 {
print("你的智商该充值")
}
for循环的应用：
百钱买白鸡游戏 ocr图片识别软件
GET: 穷举法，穷尽所有可能性直到找到正确答案
for x in 0...20{
for y in 0...33{
let z = 100 - x - y
if 5 * x + 3 * y + z / 3 == 100 && z % 3 == 0{
print("公鸡：\(x),母鸡：\(y),小鸡:\(z)")
}
}
}
分鱼游戏
循环分支语句的练习
var total = 1
var bool = true
while bool{
// 用当次循环时total的值作为鱼的总数
var fish = total
// 假设鱼的数量足够五个人分
var isEnough = true
//通过循环模拟五个人分鱼的过程
for _ in 1...5 {
// 检查剩下的与是否够分
if (fish - 1) % 5 == 0 {
fish = (fish - 1) / 5 * 4
}
else{
// 如果鱼不够分就将isEnough赋值为false并提前结束分鱼的循环
isEnough = false
bool = true
}
}
if isEnough{
print(total)
bool = false
}
total += 1
}
数组的应用：提高代码质量
func roll() ->Int{
return Int(arc4random_uniform(6))+1
}
//定义一个放整数的数组（6个元素，初始值都为0）
var f = [Int](count: 11, repeatedValue: 0)//var f: [Int]
for _ in 0..<600000{
let face = roll() + roll()
f[face - 2] += 1
}
for i in 0..<f.count{
print("\(i+2)点摇出了\(f[i])次")
}
用图片做出动画效果
//核心代码：
var imageView: UIImageView!
let screenHeight = self.view.bounds.size.height
imageView = UIImageView(frame: CGRectMake(0, screenHeight / 2 - 50, 75, 100))
// imageView.backgroundColor = UIColor.clearColor()
// imageView.image = UIImage(named: "runner0")
imageView.animationImages = [
UIImage(named: "runner0")!,
UIImage(named: "runner1")!,
UIImage(named: "runner2")!,
UIImage(named: "runner3")!,
UIImage(named: "runner4")!,
UIImage(named: "runner5")!
]
imageView.animationDuration = 0.6
self.view.addSubview(imageView)
imageView.startAnimating()
timer = NSTimer.scheduledTimerWithTimeInterval(0.1, target: self, selector: "runForward", userInfo: nil, repeats: true)
imageView.animationImages = []如果用了这句话那么下面那句话也得用
imageView.startAnimating()//不要这句话程序会报错
func runForward() {
var frame = imageView.frame//图片的另一个属性
frame.origin.x += 12
imageView.frame = frame//这句话必须写不然图片不会移动的
if frame.origin.x > self.view.bounds.size.width {
frame.origin.x = -75
imageView.frame = frame
}
}
剪刀石头布用case 语句写法 加 元组
//剪刀1石头2布3
//repeat{
// let machine = Int(arc4random_uniform(3)) + 1
// print("请出拳：",terminator:" ")
// let me = inputInt()
// if me > 0 && me < 4{
// switch (machine,me){
// case (1,1),(2,2),(3,3):
// print("平局")
// case (1,2),(2,3),(3,1):
// print("ren赢")
// default:
// print("ren输")
// }
// }
//else{
// print("输入错误")
// }
//}while true
