swift基础

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import UIKit

//TODO:----------第一讲 （String 字符串

let tempValue = 34

var str = String();

str = "Hello World \(String(tempValue))"

//验证是否为空

if str.isEmpty

{

    println("str is nil")

}

var count = countElements(str) //字符串长度

var greetiong = str.capitalizedString  //capitalizedString

var upper =  str.uppercaseString  //转换成大写

//TODO:----------第二讲 （tuple 元组）

/*

将多个值合并为单个值，元组内的值可以是任意类型

*/

let tupleValueCode : Int = 404

let tupleValueString : String = "失败"

let httpError = (tupleValueCode , tupleValueString);

println("the status is    \(httpError.0)")

println("the message is   \(httpError.1) ")

println("the httpError is \(httpError)")

let httpStatus = (statusCode:200,statusMessage:"成功")

println("the status is    \(httpStatus.statusCode)")

println("the message is   \(httpStatus.statusMessage) ")

println("the httpError is \(httpStatus)")

//TODO:----------第三讲 （Optional 可选类型）

/*

它有值但是我们不确定

没有任何值

*/

let tempStr = "123"

let optionalStr : Int? = tempStr.toInt(); //字符串可能是整形数据

if optionalStr == nil{

    

    println("tempStr = \(tempStr) 不是 整形")

}else{

    println("tempStr = \(optionalStr!) 是 整形");

    

}

//TODO:----------第四讲 （Array 数组）

//初始化

var list1 = ["value1","value2","value3"];

//数组追加

list1.append("value4");

list1+=["value5"];

//数组长度

println("list1 is count :  \(list1.count)")

//数组插入

list1.insert("value0", atIndex: 0);

//数组删除

list1.removeAtIndex(0);

println("list1 is content : \(list1)");

//数组遍历

for valueKey in list1     //(1)

{

    println("\(valueKey)")

}

for (index , value) in enumerate(list1){  //(2)

    println("\(index + 1):\(value)");

}

//TODO:----------第五讲 （Dictionary 字典）

//初始化

var dic :Dictionary<String,String> = ["key1":"value1","key2":"value2"]

//字典追加数据

dic["key3"] = "value3"

println("\(dic)")

//字典删除数据

if let removeValue = dic.removeValueForKey("key1"){

    println("remove is : \(removeValue)")

    

}

println("dic content is : \(dic)")

//字典长度

println("dic is count : \(dic.count)")

//字典便利

for (dicKey, dicValue) in dic//(1)利用元素（同时遍历key和value）

{

    println("key is content: \(dicKey)");

    println("value is content : \(dicValue)");

}

for dicKey in dic.keys  //(2)遍历key

{

    println("key is content : \(dicKey)");

}

for dicValue in dic.values  //(3)遍历value

{

    println("value is content : \(dicValue)");

}

let keys = Array(dic.keys); //(5)获取所有Key

let values = Array(dic.values); //(6)获取所有value

//TODO:----------第六讲 （控制语句）

//分支语句

if 3 > 4{

    

} else if 3 == 4{

    

} else {

    

}

         /*   Switch(1)   */

let switchTest: Character = "e"

switch switchTest{

case "a","b":

    println(" \"a\",\"b\" is to \(switchTest)")

case "c","e":

    println(" \"c\",\"e\" is to \(switchTest)")

default:

    println("default is to \(switchTest)")

}

         /*   Switch(2)   */

let switchTestCount = 3_000

let switchTestStr = " stars in the miky way"

var naturalCount:String

switch switchTestCount {

case 0:

    naturalCount = "no"

case 1...3:

    naturalCount = "a few"

case 4...9:

    naturalCount = "seeral"

case 10...99:

    naturalCount = "hundreds of"

case 100...999_999:

    naturalCount = "thousands of"

default:

    naturalCount = "default"

}

println("There are \(naturalCount + switchTestStr)")

//循环语句

         /*while 水仙花数  */

var i = 100

var r = 0  //计算百位数

var s = 0  //计算十位数

var t = 0  //计算个位数

while i < 1000 {

    r = i / 100

    s = (i - r * 100 ) / 10

    t = i - r * 100 - s * 10

    if ( i == r * r * r + s * s * s + t * t * t) {

        println("i = \(i)");

        

    }

    i++

}

         /* do...while 水仙花数  */

i = 100

r = 0  //计算百位数

s = 0  //计算十位数

t = 0  //计算个位数

do {

    r = i / 100

    s = (i - r * 100 ) / 10

    t = i - r * 100 - s * 10

    if ( i == r * r * r + s * s * s + t * t * t) {

        println("i = \(i)");

        

    }

    i++

}while i < 1000

         /* for */

var forCount = 8

var rr = 0

var ss = 0

for var index = 0 ; index < forCount ; index++ {

    rr = index * index

    ss = rr * index

    

    println("》》》》》》》》》》》》》》》》》》")

    println("整数为 : \(index)")

    println("对应平方和 : \(rr)")

    println("对应立方和 : \(rr)")

}