Swift学习第一天--面向过程

//: Playground - noun: a place where people can play

import UIKit

//---------------------- Hello world ----------------------

var str = "Hello, playground"

print("Hello world and " + str)
print("您好")



//---------------------- 数据类型 ----------------------

//整型与浮点型
let age = 24
let pi = 3.14
print(Int.max)
print(Int.min)


//自动类型推断
var name : String = "fengdianlong"
var count : Int = 10
var mount = 10  //类型推断（声明遍历时不用指定类型）


//元组
var valueTuple = ("feng",24,"shandongjinan","山东大学威海校区")
print(valueTuple.0)
print(valueTuple.1)
print(valueTuple.2)
print(valueTuple.3)

var namevalueTuple = (name:"fengdianlong",age:24)
print(namevalueTuple.name)


//Optional可选类型
var address :String?
address = "shandongjinan"



//---------------------- 运算符 ----------------------
//算数运算符
print(100/10)
print(7%3)
print(3*4)
print(5+3)

//组合赋值运算符
var a = 10
a += 4
print(a)

//比较运算符
print(1>1)
print(3>=9)

//逻辑运算符
print("feng"=="long" || "feng"=="feng")
print(true && false)
print(true || false)
print(!true)


//---------------------- 字符串 ----------------------
var str1 = ""
var str2 = "  "

str1.isEmpty
str2.isEmpty

var wo = "W"  //默认为字符串
var me : Character = "m"   //指定为字符

//遍历字符串
var words = "这里是我的字符串"
for word in words.characters {
    print(word)
}

//字符串 + 字符串
let swiftstring1 = "Malcolm "
let swiftstring2 = "Feng"
var swiftstring = swiftstring1 + swiftstring2
swiftstring.append("hahahah")

//字符串插值
let sir = "Malcolm"
let type = "G"
let number = "11"
let price = 1538.6

let message = "\(sir)先生，您订购了\(type)\(number)的往返机票，总价为：\(price * 2)"

//---------------------- 数组 ----------------------

let array1 : [Int] = [Int](repeatElement(3, count: 10))

let array2 = Array(1...10)

var places = ["beijing","shanghai","wuhan","zhejiang","jiaxing"]

places.count
places.isEmpty
places.append("jinan")
places += ["weihai","qingdao","yaoqang"]

places[1]

places.insert("xuanjie", at: 1)

places.remove(at: 2)
//places.removeFirst()
//places.removeLast()
//places.removeAll()

places.contains("jinan")

places.sort()
places.sorted()

//---------------------- 字典 ----------------------

var students = ["name":"fengdianlong", "age":"24", "address":"shandongjinan"]

students.count
students.isEmpty


students["address"] = "beijing" //修改

students["name"]

for (key,value) in students {
    print(key,value)
}

for key in students.keys {
    print(key)
}

let keys = [String](students.keys) //提取keys到一个数组


//---------------------- 控制语句 ----------------------
for _ in 1...10{
    print("1")
}

var sum = 0
for i in 1...100{
    sum += i
}
sum

var money = false
if(money){
    print("注孤生")
}else{
    print("找个女朋友")
}


var temp = 50
switch temp {
case 40...50:
    print("热死人了")
default:
    print("还活着")
}



//---------------------- 函数 ----------------------

func addCount(a:Int, b:Int) -> Int{
    return a + b
}

// 调用
var aaa = addCount(a: 7, b: 8)


// 多返回值
func maxMin() -> (Int, Int){
    return (Int.min, Int.max)
}

// 默认参数
func function(a:Int, increment:Int = 3) -> Int{
    return a + increment
}

// 函数类型参数
func calculate(x:Int, y:Int, method:(Int,Int) -> Int ) -> Int{
    return method(x,y)
}

func add(x:Int,y:Int) ->Int{
    return x + y
}
func multiply(x:Int,y:Int) ->Int{
    return x * y
}



//---------------------- 枚举 ----------------------
enum Weather{
    case sunny
    case cloudy
    case froggy
    case snow
    case rainy
}

Weather.sunny