swift-字典

swift字典

• 在swift中，key：key值一定是可hash的，一定是独一无二的，swift的基本数据类型（String,Int,Float）都是可哈希的，所以都可以作为key值。 value：没有要求

• 直接上代码了,注释给大家标的很明白

    //创建字典并赋值
    let dict = ["name":"xiaoyu","age":12]
    let dict2:[String:Any] = ["name":"xiaoyu","age":12];
    let dict3:Dictionary<String,Any> = ["name":"xiaoyu","age":13,"height":130]
  
    print(dict3)
  
    //创建空字典
  
    let dict4:[String:Any] = [:]
    let dict5:[String:Any] = Dictionary()
  
    //创建可变字典
    var dict6:[String:Any] = ["name":"xiaoyu"]
  
    //更新字典的数据 value输出的是原来的key对应的value值
    if let Value = dict6.updateValue("dayu", forKey: "name")
    {
        print(Value)
        print(dict6)
    }
  
    //删除字典元素
    dict6.removeValueForKey("name")
    //删除全部元素
    dict6.removeAll()
    dict6.removeAll(keepCapacity: true)
    //遍历字典
    for (key,value) in dict6
    {
        print("key:\(key) value:\(value)")
    }
  
    for key in dict6.keys{
        print("key:\(key)")
    }
  
    //合并字典
  
    var dict7:[String:Any] = ["name":"小雨","age":133]
  
    var newDict8:[String:Any] = ["weight":"小于","height":13]
    for (key,value) in newDict8{
        dict7.updateValue(value, forKey: key)
    }
  
    print("dict7:\(dict7)");