SafeDictionary

This is a safe, simple, lightweight dictionary object that does not throw exceptions, useful for parsing JSON.

Usage

Take the following JSON, for example:

{
  "success" : true,
  "code" : 200,
  "message" : "Success!",
  "result" : {
    "numberOfUnicorns" : 4,
    "names" : [
      "Unicorn One",
      "Unicorn Three",
      "Unicorn Tricorn",
      "Unicorn Popcorn",
    ]
  }
}

A new SafeDictionary can be initialized using SafeDictionary(rawJSON: String), SafeDictionary(rawJSON: [String : AnyObject]?), SafeDictionary(fromData: Data?), or using SafeDictionary(value: NSDictionary?)

To go deeper into the JSON tree, just index the object using ["key"] or [numberKey]. To get the value at the current index, use the variables .boolean, .number, .string, .arrayOfDictionaries, etc.

let dict: SafeDictionary

//all of these will return nil if not found
dict.string //String?
dict.boolean //Bool?
dict.number //Int?
dict.cgFloat //CGFloat?
dict.dictionary //[String : AnyObject]?
dict.cocoaDictionary //NSDictionary?
dict.image //UIImage?
dict.array //[AnyObject]?
dict.arrayOfDictionaries //[SafeDictionary]?
dict.object //AnyObject?

For example, let's use let dict: SafeDictionary to represent the JSON above

dict["success"]?.boolean //true
dict["nonExistent"]?.boolean //nil
dict["code"]?.number //200
dict["message"]?.string //"Success!"
dict["nonExistent"]?.string //nil

dict["result"]?.boolean //nil
dict["result"]?["numberOfUnicorns"]?.number //4
dict["nonExistent"]?["nonExistent"]?["stillNonExistent"]?.string //nil

dict["result"]?["names"]?.string //nil
dict["result"]?["names"]?.stringArray //["Unicorn One", "Unicorn Three", "Unicorn Tricorn", "Unicorn Popcorn"]
dict["result"]?["names"]?[0] //"Unicorn One"
dict["result"]?["names"]?[3] //"Unicorn Popcorn"
dict["result"]?["names"]?[4] //nil

.arrayOfDictionaries can be used to iterate through an array. For example, with the JSON

{
    "array" : [
        "Value One",
        "Value Purple",
        "Value Banana",
    ]
}

Taking dict as the SafeDictionary initialized with the JSON above,

let dict: SafeDictionary? = wrapped["array"]
for value in dict?.arrayOfDictionaries ?? []{
    print(", ");
    print(value?.string ?? "");
}

Will print

", Value One, Value Purple, Value Banana"