Swift基础数据类型和循环

最新推荐文章于 2025-12-21 16:40:18 发布

转载最新推荐文章于 2025-12-21 16:40:18 发布 · 72 阅读

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原文链接：http://www.cnblogs.com/asdfaa/p/3891801.html

文章标签：

#swift

本文介绍了Swift语言的基础知识，包括变量、常量、数据类型、数组、字典及循环等核心概念，并通过具体示例帮助读者理解如何使用这些基本元素。

本文是一篇swift的基础教材,讲解了swift语言的变量,数据类型和循环.准备学swift的同学可以参考学习下.

1 常量变量

    var myVariable = 42 //变量
    myVariable = 50
    let myConstant = 42 //常量

2 显示指明变量类型

let explicitDouble: Double = 70

3 数组和字典

    var shoppingList = ["catfish", "water", "tulips", "blue paint"]
    shoppingList[1] = "bottle of water"

    var occupations = [
        "Malcolm": "Captain", //前面是key 后面是value
        "Kaylee": "Mechanic",
    ]
    occupations["Jayne"] = "Public Relations"

4 创建初始化数组和字典

let emptyArray = String[]()
let emptyDictionary = Dictionary<String, Float>()

5数组添加

var emptyarry = String[]()
emptyarry.append("dfd")

6 for循环

    let sss = [11,12,43,554,12,434]
    for i in 0..4 {
         print("(i) = (sss[i])");
             print("n");
          }
    for i in sss{
          print(i);
             print("n");
          }

7 switch

    let vegetable = "red pepper"
    switch vegetable {
    case "celery":
        let vegetableComment = "Add some raisins and make ants on a log."
    case "cucumber", "watercress":
        let vegetableComment = "That would make a good tea sandwich."
    case let x where x.hasSuffix("pepper"):
        let vegetableComment = "Is it a spicy (x)?" fallthrough
    default:
        let vegetableComment = "Everything tastes good in soup."
    }

自：http://www.phperz.com/article/14/0802/15200.html

转载于:https://www.cnblogs.com/asdfaa/p/3891801.html