如何在Swift语言中将不同类型的字典放入字典中？

7 回答

• 0

  您可以使用 Any 类型实现类似plist的嵌套结构，用于字典值，即Swift 's somewhat counterpart to Objective-C' s id 类型，但也可以保存值类型 .

  var response = Dictionary<String, Any>()
  response["user"] = ["Login": "Power Ranger", "Password": "Mighty Morfin'"]
  response["status"] = 200
  

  编辑：

  Any 似乎比 AnyObject 好，因为在上面的代码中 response["status"] 的类型为 Swift.Int ，而使用 AnyObject 的值类型则为 __NSCFNumber .

  回复于 2024-04-27T05:02:47+08:00
• -2

  正如已经建议的那样，你可以使用 Any 类型来表示一个真正凌乱的plist字典's values. But then how do you work with the data? Cast every value any time you look it up from the dictionary? That' . 一个更好，更类型安全的方法来模拟一个plist将是利用Swift 's enums, also known as algebraic data types or discriminated unions. They let you specify exactly what types are permitted in the dictionary and avoid ever having to cast. Here'的一个实现，解释说：

  // An atomic (i.e. non-collection) data type in a plist.
  enum PListNode {
    case PLN_String(String)
    case PLN_Integer(Int)
    case PLN_Float(Double)
    case PLN_Bool(Bool)
    case PLN_Date(CFDate)
    case PLN_Data(CFData)
  }
  

  在最原子级别，只有上述数据类型可以存储在plist中 . plist中的每个'node'最终只能是这些类型中的一种 . 所以我们创建一个枚举，让我们指定它 .

  // A value that can be stored in a plist Dictionary's key-value pair.
  enum PListValue {
    case PLV_Node(PListNode)
    case PLV_Array(PListNode[])
    case PLV_Dictionary(Dictionary<String, Box<PListValue>>)
  }
  
  typealias PList = Dictionary<String, Box<PListValue>>
  

  plist基本上是键值对的字典，每个值可以是原子（即非集合）值;或者它可以是一个原子值数组;或者它可以是字符串 - plist值对的字典 . 上面的枚举表达了这些约束，而typealias为plist类型提供了一个易于记忆的名称 .

  鉴于上述类型，我们可以以类型安全的方式完全表达任何给定的plist，例如：

  // Example translated from
  // https://developer.apple.com/library/Mac/documentation/Darwin/Reference/ManPages/man5/plist.5.html
  let myPlist: PList = [
    "Year Of Birth": Box(PLV_Node(PLN_Integer(1965)))
  , "Pets Names":    Box(PLV_Array([]))
  , "Picture":       Box(PLV_Node(PLN_Data(...)))
  , "City of Birth": Box(PLV_Node(PLN_String("Springfield")))
  , "Name":          Box(PLV_Node(PLN_String("John Doe")))
  , "Kids Names":    Box(
      PLV_Array([PLN_String("John"), PLN_String("Kyra")])
    )
  ]
  

  这里的类型安全意味着您可以使用 switch 语句处理任何给定的plist并覆盖所有可能性而无需任何转换 . 您正在消除一大类潜在的运行时错误 . 例如 . ：

  // See https://developer.apple.com/library/prerelease/ios/documentation/Swift/Conceptual/Swift_Programming_Language/Enumerations.html#//apple_ref/doc/uid/TP40014097-CH12-XID_189 for explanation
  switch myPlist["Year Of Birth"] {
    case Box(.PLV_Node(let plvNodeValue)):
      ...
    case Box(.PLV_Array(let plvArrayValue)):
      ...
    case Box(.PLV_Dictionary(let plvDictionaryValue)):
      ...
  }
  

  请注意，有必要将递归数据结构包装在“框”（指向实际值的指针）中，以保持其大小有限 .

  回复于 2024-04-27T05:02:47+08:00
• 2

  NSObject适用于我的情况，而“Any”则不适用

  var d:Dictionary<String,NSObject> = [:]
  d["key1"] = "ddd"
  d["key2"] = 111  //OK
  NSLog("%@", d) //OK
  
  var d2:Dictionary = Dictionary<String,Any>()
  d2["key1"] = "ddd"
  d2["key2"] = 111
  NSLog("%@", d2) //I got error here
  

  回复于 2024-04-27T05:02:47+08:00
• 11

  使用：Dictionary <String，AnyObject>

  var dict: Dictionary<String, AnyObject> = [
      "number": 1,
      "string": "Hello",
  ]
  

  回复于 2024-04-27T05:02:47+08:00
• 1

  像这样使用NSMutableDictionary：

  var dictInfo : NSMutableDictionary = [ "lang_key": "1"]
      dictInfo["food_type"]     =   lbl_TypeOfFood.text
      dictInfo["search_text"]   =   txt_Search.text
      dictInfo["date"]          =   lbl_Date.text
      dictInfo["opening_hours"] =   lbl_OpeningHours.text
  

  希望这会好起来的 .

  回复于 2024-04-27T05:02:47+08:00
• 90

  NSMutableDictionary to Dictionary works like a charm and will allow you to put different types in a Dictionary in the Swift Language:

  let nsMutableDictionary = NSMutableDictionary()
  nsMutableDictionary[NSFontAttributeName] = UIFont(name: "HelveticaNeue", size: 12.0)!
  nsMutableDictionary[NSForegroundColorAttributeName] = UIColor.redColor()
  
  let dictionary: Dictionary<NSObject, AnyObject> = nsMutableDictionary
  
  self.attributedPlaceholder = NSAttributedString(string: textParam, attributes: dictionary)
  

  回复于 2024-04-27T05:02:47+08:00
• 1

  let dictionary : Dictionary = [
      "key": "value",
      "key2": 2,
      "key3": NSString(),
      2: "test",
  ]
  

  可以指定限制字典的类型

  let dictionary : Dictionary<String, String> = [
      "key": "value",
      "key2": 2, // This errors
  ]
  

  回复于 2024-04-27T05:02:47+08:00