字典:
// // main.swift // 字典 // // Created by Mac on 15-9-9. // Copyright (c) 2015年 青苹果. All rights reserved. // import Foundation //字典是无序的 var dic:[String:String] = ["key1":"value1","key2":"value2"] println("\(dic)") var a1:(NSInteger) = dic.count //移除指定key的健值队 dic["key1"] = nil println("\(dic)") //添加健值对 dic["key1"] = "value1" println("\(dic)") //修改指定key的value dic["key1"] = "zhang" println("\(dic)") //创建一个空的字典 var dic1:[String:String] = [:] println("\(dic1)") //判断健值对是否为空,然后移除 if var key = dic.removeValueForKey("key1") { dic.removeValueForKey("key1") println("\(dic)") } //判断健值对是否存在 if var key = dic["key1"]{ println("\(key)") }else{ println("空") } //移除所有健值对 //dic.removeAll(keepCapacity: true) //println("\(dic)") //字典的遍历,字典是无序的 for (key,value) in dic{ println("\(key):\(value)") } var a5 = [:] for a5 in dic{ println("\(a5)") } //遍历所有的key for key in dic.keys{ println("\(key)") } var a3 = "" for a3 in dic.keys{ println("\(a3)") } //遍历所有的value for value in dic.values{ println("\(value)") } var a4 = "" for a4 in dic.values{ println("\(a4)") } //取出所有的key var arrayKey = Array(dic.keys) println("\(arrayKey)") //取出所有的value var arrayValue = Array(dic.values) println("\(arrayValue)")循环得使用方法:
// // main.swift // 循环练习-01 // // Created by Mac on 15-9-8. // Copyright (c) 2015年 青苹果. All rights reserved. // import Foundation var j = 0 //for循环得结构方式 for j in (0...15){ println("\(j)") } for var k = 0;k<100;++k{ println("\(k)") } for var k1 = 0;k1<100;k1=k1+2{ println("k1 ==\(k1)") } //创建不包含上限得范围 for var i1 = 0;i1>=0;++i1{ if i1 > 1000{ break } println("i1=\(i1)") } //while循环 var i2 = 0 while i2<100{ i2++; println("i2=\(i2)") } //do while循环 var i3 = 0 do{ i3++ println("i3=\(i3)") }while i3<100 var i4=0 for var j1=0;j1<10;j1=j1+1{ for var j2=0; j2<10; ++j2{ i4++; println("\(i4)") } }
转载于:https://www.cnblogs.com/zxh-iOS/p/4860109.html