Generating a JSON-Array and converting it to a Base64-String - arrays

Question

I'm trying to create a Base64-String in Swift. I have an example of a Base64-encoded string and its array-counterpart. My problem now is, that I don't know how I get an equivalent array to the one which is given in the example.
Because I didn't want to mess around in my XCode-project I did the following in a playground.
given array:
{"WHERE":{"Class":"%3f","Location":"3b"},"ORDER":["Day ASC","Location DESC"]}
given Base64-string:
eyJXSEVSRSI6eyJDbGFzcyI6IiUzZiIsIkxvY2F0aW9uIjoiM2IifSwiT1JERVIiOlsiRGF5IEFTQyIsIkxvY2F0aW9uIERFU0MiXX0=
First I'm decoding the example-string
let str = "eyJXSEVSRSI6eyJDbGFzcyI6IiUzZiIsIkxvY2F0aW9uIjoiM2IifSwiT1JERVIiOlsiRGF5IEFTQyIsIkxvY2F0aW9uIERFU0MiXX0="
let data = NSData(base64EncodedString: str, options: NSDataBase64DecodingOptions(rawValue: 0))
do {
let result = try NSJSONSerialization.JSONObjectWithData(data!, options: .AllowFragments)
} catch let error {
print(error)
}
//"result" is ["WHERE": ["Class": "%3f", "Location": "3b"], "ORDER": ["Day ASC", "Location DESC"]]
Below I'm trying to reproduce the string from above
var array = [String : AnyObject]()
var arrayPartA = [String : String]()
arrayPartA["Class"] = "%3f"
arrayPartA["Location"] = "3b"
array["ORDER"] = ["Day ASC", "Location DESC"]
array["WHERE"] = arrayPartA
array //The playground says that "array" is ["ORDER": ["Day ASC", "Location DESC"], "WHERE": ["Class": "%3f", "Location": "3b"]]
//"ORDER" and "WHERE" are switched but I don't get them to be at the right position
let utf8str2: NSData = String(array).dataUsingEncoding(NSUTF8StringEncoding)!
let encodedStr = utf8str2.base64EncodedStringWithOptions(NSDataBase64EncodingOptions(rawValue: 0))
//Here "encodedStr" is WyJPUkRFUiI6ICgKICAgICJEYXkgQVNDIiwKICAgICJMb2NhdGlvbiBERVNDIgopLCAiV0hFUkUiOiB7CiAgICBDbGFzcyA9ICIlM2YiOwogICAgTG9jYXRpb24gPSAzYjsKfV0=
//but it should be eyJXSEVSRSI6eyJDbGFzcyI6IiUzZiIsIkxvY2F0aW9uIjoiM2IifSwiT1JERVIiOlsiRGF5IEFTQyIsIkxvY2F0aW9uIERFU0MiXX0=
I would be glad if someone could explain to me what I'm doing wrong and how I can reproduce the given Base64-string.
Since I'm new to this website I apologize in advance for wrong layout or other possible conventions I don't know.

Answer 1

Could you try this please? Is this what you wanted to do? It should convert a Dictionary to base64 String
func jsonToBaseString (yourJSON: [String: String]) -> String? {
do {
let jsonData = try JSONSerialization.data(withJSONObject: yourJSON, options: JSONSerialization.WritingOptions.prettyPrinted)
return
jsonData.base64EncodedString(options: .endLineWithCarriageReturn)
} catch {
return nil
}
}
Dictionary is Swifts JSON representation...

Answer 2

Two important things to understand:
What you are calling an array is not an array, it's a JSON dictionary (containing an array for the ORDER key).
Be careful not to confuse the syntax of arrays and dictionaries between Swift and JSON.
In Swift, an array: [0, 1], a dictionary: ["a":0, "b":1].
In JSON, an array: [0, 1], a dictionary: {"a":0, "b":1}.
A Swift dictionary is an unordered collection. There's no "position" for key-value pairs.

Answer 3

You'll need to change several things:
Your input string (not serialized) is not an array, but a JSON object.
Try constructing your string with a proper JSON library, such as SwiftyJSON.
String(array) is not enough to consistently convert your objects to strings. You should use a JSON serializer (such as SwiftyJSON json.rawString()).

Answer 4

let follow recommendation to use some json serialization, but take in account that
{
"alfa": 1,
"beta": true
}
and
{"beta":true,"alfa":1}
represents in JSON notation the same object even though their string representation ( doesn't matter if base64 encoded or not ) are different.