swift3.0 字典的基本用法

自学swift3.0,如果有什么错误或建议的话欢迎吐槽哦~

        //1.字典的定义使用[key:value,key:value]快速定义
        let dic:[String:Any] = ["name":"张三","age":22]
        print(dic)
        
        //数组字典
        let arrDic:[[String:Any]] = [
            ["name":"张三","age":22],
            ["name":"李四","age":24]
        ]
        print(arrDic)
        //2.可变字典的增删改查
        var dictionary:[String:Any] = ["name":"张三","age":22]
        print(dictionary)
        
        /*
         key存在则为修改,key不存在 则为添加
         */
        //增加键值对
        dictionary["score"] = 99
        print(dictionary)
        
        //修改键值对
        dictionary["age"] = 33
        print(dictionary)
        
        //删除键值对
        // ps: 字典是通过KEY来定位值的,所有的KEY必须是可以 hash/哈希 的 (md5就是一种哈希,哈希就是将字符串变成唯一的整数,便于查找,能够提高字典遍历的速度)
//        dictionary.removeValue(forKey: <#T##Hashable#>)
        
        dictionary.removeValue(forKey: "score")
        print(dictionary)
        
        //字典遍历
        //写法一
        for e in dictionary {
            print("key = \(e.key)   value = \(e.value)")
            
        }
        
        //写法二
        for (key,value) in dictionary {
            print("key = \(key)   value = \(value)")
        }
        
        //字典合并
        var dic1 = ["name":"小明","score":"88"]
        print(dic1)
        let dic2 = ["teacher":"老大"]
        
        for (key,value) in dic2 {
            dic1[key] = value
        }
        print(dic1)



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转载自blog.csdn.net/loveLittleKid/article/details/52944507