//: Playground - noun: a place where people can play@H_301_1@

@H_301_1@

import UIKit@H_301_1@

@H_301_1@

var str = "Hello,playground"@H_301_1@

var myVar = 45@H_301_1@

myVar = 90@H_301_1@

let myCon = 90@H_301_1@

@H_301_1@

let implictInteger = 70@H_301_1@

@H_301_1@

let implicitDouble = 80.0@H_301_1@

@H_301_1@

let explicitDouble: Double = 700@H_301_1@

@H_301_1@

let expFloat: Float = 4@H_301_1@

//值永远不会隐式转换为另一种类型。如果你需要把一个值转换到不同类型,需要明确的构造一个所需类型的实例。@H_301_1@

let label = "The width is "@H_301_1@

@H_301_1@

let width = 100@H_301_1@

@H_301_1@

let widthLabel = label + String(width)@H_301_1@

//实现字符串中包含值：以小括号来写值，并用反斜线(\)放在小括号之前@H_301_1@

let apples = 3@H_301_1@

@H_301_1@

let oranges = 5@H_301_1@

@H_301_1@

let appleSummary = "I have \(apples) apples."@H_301_1@

@H_301_1@

let fruitSummary = "I have \(apples + oranges) pieces"@H_301_1@

@H_301_1@

let impdouble = 90.0@H_301_1@

@H_301_1@

let tom = "name"@H_301_1@

@H_301_1@

let labe = "go to \(impdouble) \(tom) fname"@H_301_1@

//创建一个数组和字典使用方括号"[]"，访问其元素则是通过方括号中得索引或键。@H_301_1@

var shoppingList = ["catish","water","tulips","blue paint"]@H_301_1@

@H_301_1@

shoppingList[1] = "bottle of water"@H_301_1@

@H_301_1@

var occupations = [@H_301_1@

"Malcolm": "Captain",@H_301_1@

"Kaylee": "Mechanic",@H_301_1@

]@H_301_1@

occupations["Jayne"] = "Public Re"@H_301_1@

//创建一个空得数组或字典，使用初始化语法：@H_301_1@

let emptyArray = [String]()@H_301_1@

@H_301_1@

let emptyDictionary = Dictionary<String,Float>()@H_301_1@

//如果类型信息无法推断,你可以写空的数组"[]" 和空的字典"[:]",例如你设置一个知道变量并传入参数到函数:@H_301_1@

shoppingList = []@H_301_1@

occupations = [:]@H_301_1@ @H_248_301@ //数字字面量(Literals)@H_301_1@

var decimalInteger = 17//十进制@H_301_1@

var binarryInteger = 0b10001//二进制@H_301_1@

let octalInteger = 0o21//八进制@H_301_1@

let hexadecimalInteger = 0x11//十六进制@H_301_1@

//可选值绑定@H_301_1@

var temp1: String? = "123"@H_301_1@

if let temp2 = temp1?.toInt() {@H_301_1@

println("\(temp1) has an \(temp2)")@H_301_1@

}@H_301_1@