Weird sorting when parsing JSON

Question

I am working on an App and I use my JSON RESTful API. Therefor I parse JSON like in the following example:

NSData * apiReturn;
NSError *myError = nil;
NSDictionary *res = [NSJSONSerialization JSONObjectWithData:apiReturn options:NSJSONReadingMutableLeaves error:&myError];

If I now pass the following JSON encoded String via the API to the App:

{"da": {"name":"dienstlicher Anlass", "duty":true, "type":"dropdown", "values":{"gt":{"name":"Gesprächstermin", "recurring":true, "values":{"fa":{"name":"Firma", "duty":true, "type":"text", "multiline":false}, "ar":{"name":"Anrede", "duty":true, "single":true, "type":"checkbox", "values":{"fr":{"name":"Frau"}, "hr":{"name":"Herr"}}}, "nm":{"name":"Gesprächspartner", "duty":true, "type":"text", "multiline":false}, "bm":{"name":"Bemerkung", "duty":false, "type":"text", "multiline":true}}}} },"bm":{"name":"Bemerkung", "values":[], "type":"text"},"bm2":{"name":"Bemerkung", "values":[], "type":"text"}}

(You can parse this a bit prettier here: http://json.parser.online.fr)

The NSDictionary should contain the following Keys: "da", "bm", "bm2" - Sorted this way, because this is the sorting of the JSON String!

But what Objective-C does, is this:

Why does Objective-C sort the elements, and why so wrong?

I hope you can help! :)

A JSON "object" (dictionary) does not guarantee that entry order is maintained. — Hot Licks, Jul 27 '15 at 14:29

score 3 · Accepted Answer · answered Jul 27 '15 at 14:08

3

An NSDictionary is not guaranteed to store the keys in any given order.

answered Jul 27 '15 at 14:08

The dude

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Do you know any alternative? – Christopher Mäuer Jul 27 '15 at 14:09
You can use this alternative : http://stackoverflow.com/questions/3583020/can-i-sort-the-nsdictionary-on-basis-of-key-in-objective-c – CRDave Jul 27 '15 at 14:10
@ChristopherMäuer check this out: http://stackoverflow.com/questions/376090/nsdictionary-with-ordered-keys – The dude Jul 27 '15 at 14:11
If I am not wrong, this will sort the elements by their name? This is not what I want! – Christopher Mäuer Jul 27 '15 at 14:11
@ChristopherMäuer I think that if you care about order, you should be using arrays – The dude Jul 27 '15 at 14:12
Maybe I should add a value "sorting" to it with an Integer, and the sort with the method @CRDave wrote? – Christopher Mäuer Jul 27 '15 at 14:13
Is it possible to parse JSON to an Array, because whatever I do, it will give me a NSDictionary! – Christopher Mäuer Jul 27 '15 at 14:18
1

@ChristopherMäuer It's giving you a dictionary because you're feeding it a dictionary. Each element at the `values` key in your JSON is an array, use that for reference. – rebello95 Jul 27 '15 at 14:19

Weird sorting when parsing JSON

1 Answers1