swift NO.1
// Playground - noun: a place where people can play
swift2.2 NO.1
import UIKit
var str = "Hello, playground"
// Playground - noun: a place where people can play
//
print("Hello,world")
//
var myVariable=42
myVariable=50
let myConstant=43
//
let implicitInteger=70
let implicitDouble=70.0
或者
let explicitDouble:Double=70
//
let label="The width is "
let width=94
let widthLabel=label+String(width)
//
let apples=3
let oranges=5
let appleSummary="I have \(apples) apples."
let fruitSummary="I have \(oranges) oranges."
///
///
var shoppingList=["catfish","water","tulips","blue paint"]
shoppingList[1]="bottle of water"
var occupations=["Malclm":"Caption","Kalyee":"Mechanic"]
occupations["Jayne"]="Public Relations"
println(occupations["Jayne"])
//
shoppingList=[]
occupations=[:]
//
let individualScores=[75,43,103,87,12]
var teamScore=0
for score in individualScores{
if score>50{
teamScore+=4
}
else
{
teamScore+=1
}
}
println(teamScore)
//
var optionalstring:String?="Hello "
println(optionalstring == nil)
var optionalName:String?="John Appleseed"
var greeting="Hello!"
if let name = optionalName
{greeting="Hello,\(name)"}
//
let nickName:String?=nil
let fullName:String="John Appleased"
let informalGreeting="Hi \(nickName ?? fullName)"
////good example
let vegetable = "red pepper"
switch vegetable {
case "celery":
println("Add some raisins and make ants on a log.")
case"cucumber","watercress":
println("That would make a good tea sandwich.")
case let x where x.hasSuffix("pepper"):
println("Is it a spicy \(x)?" )
default:
println("Everything tastes good in soup.")
}