Swift學習——使用if和switch來進行條件操作，使用for,while,和do-while來進行迴圈(三)

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Swift學習——使用if和switch來進行條件操作，使用for,while,和do-while來進行迴圈

//switch支援任意類型的資料以及各種比較操作——不僅僅是整數以及測試相等

//注意如果去掉default程式會報錯

let strings = "hello3"switch strings{    case "hello1":    let stringsComment = "say hello1"    println("stringsComment is \(stringsComment)")    break    case "hello2","hello3":    let stringsComment = "say hello2 and hello3"    println("stringsComment is \(stringsComment)")    break    case let x where x.hasSuffix("hello4"):    let stringsComment = "Is it a spicy \(x)?"    println("stringsComment is \(stringsComment)")    break    default:    let stringsComment = "say everything"    println("stringsComment is \(stringsComment)")}

簡單的while和do-while迴圈

// while迴圈var n = 3while n < 100{    n = n*2}println("n is \(n)")//do-while迴圈var m = 3do{    m = m*2}while m < 100println("m is \(m)")

列印結果

stringsComment is say hello2 and hello3

n is 192

m is 192