//声明字典
let demoDict1 = ["demoKey": "demoValue"] //声明一个常量字典
var demoDict3 = ["sexual": "male", "age": 18] as [String: Any] //声明一个多型变量字典
//添加字典内元素
demoDict3["height"] = 180
demoDict3["weight"] = 85.5
//删除字典内元素
demoDict3.removeValue(forKey: "height") //删除元素
demoDict2.removeAll() //全部删除
//修改字典内元素
demoDict3["name"] = "Mike"
//获取某一个元素
demoDict3["sexual"]
//遍历字典中的所有键
for key in demoDict3{
print(key)
}
//遍历字典中的所有值
for value in demoDict3{
print(value)
}
//遍历字典中的所有键值对
for (key, value) in demoDict3{
print(key)
print(value)
}
//字典合并
for (key, value) in demoDict1.reversed(){
demoDict3[key] = value
}
demoDict3
var demoDict2 = ["name": "Michael"] //声明一个变量字典
图片发自简书App
