如何使用swift中的Dictionary

本篇内容主要讲解"如何使用swift中的Dictionary"，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习"如何使用swift中的Dictionary"吧!

定义

//定义var dic1 = Dictionary()var dic2 = [String: Int]()var dic3: Dictionary = [:]var dic = ["zhang san": 18, "li si": 19, "wang wu": 20]

是否为空 & 元素数量

print(dic.isEmpty)//falseprint(dic.count)//3

遍历

//无序遍历字典for (key, value) in dic {    print("name: \(key), age:\(value)")}/*name: li si, age:19name: wang wu, age:20name: zhang san, age:18*///有序遍历for key in dic.keys.sorted() {    print("name: \(key), age:\(dic[key]!)")}/*name: li si, age:19name: wang wu, age:20name: zhang san, age:18*/

update

//updatedic["zhang san"] = 19print(dic)//["li si": 19, "wang wu": 20, "zhang san": 19]//updateValuedic.updateValue(20, forKey: "zhang san")print(dic)//["li si": 19, "wang wu": 20, "zhang san": 20]

remove

//removedic["zhang san"] = nilprint(dic)//["li si": 19, "wang wu": 20]//removeValueprint(dic.removeValue(forKey: "li si"))//Optional(19)print(dic)//["wang wu": 20]

merge

//mergevar mergeDic = ["a": 1, "b": 2]mergeDic.merge(["a": 3, "c": 4]) { (current, _) in current }print(mergeDic)//["c": 4, "a": 1, "b": 2]mergeDic.merge(["a": 3, "d": 6]) { (_, new) in new }print(mergeDic)//["b": 2, "c": 4, "a": 3, "d": 6]

到此，相信大家对"如何使用swift中的Dictionary"有了更深的了解，不妨来实际操作一番吧！这里是网站，更多相关内容可以进入相关频道进行查询，关注我们，继续学习！