swift 字典

//1. 如何定义字典
//1)定义不可变字典，使用let修饰
let a : Int = 8

let dict = ["name":"hao", "vegetable":"cabbage"]  //不需要进行转化
let dict2 = ["name":"you", "weight":50] as [String : Any]

let dict3 : Dictionary<String,Any> = ["name":"you", "weight":50]
let dict4 : [String:Any] = ["name":"you", "weight":50]

//2.定义可变：用var修饰
var dicM = Dictionary<String,Any>()
var dicM2 = [String:Any]()

//3.对可变数组的基本操作: 增删改查
dicM["name"] = "you"
dicM["age"] = 12

dicM.removeValue(forKey: "name")

dicM["age"] = 89

dicM["age"]

//4.遍历数组
for key in dicM.keys {
    print(key)
}

for value in dicM.values {
    print(value)
}

for (key, value) in dicM {
    print("\(key) : \(value)")
}