I get from an URL this result :
NSString *result = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
it looks like this :
[{"modele":"Audi TT Coup\u00e9 2.0 TFSI","modele_annee":null,"annee":"2007","cilindre":"4 cyl","boite":"BVM","transmision":"Traction","carburant":"ES"},
{"modele":"Audi TT Coup\u00e9 2.0 TFSI","modele_annee":null,"annee":"2007","cilindre":"4 cyl","boite":"BVM","transmision":"Traction","carburant":"ES"}]
So it contains 2 dictionaries. I need to take the objects from all the keys from this result. How can I do this?
I tried this : NSDictionary vehiculesPossedeDictionary=(NSDictionary *)result;
and then this : [vehiculesPossedeDictinary objectForKey:#"modele"]; but this is not working.
Please help me... Thanks in advance
What you have is a JSON string which describes an "array" containing two "objects". This needs to be converted to Objective-C objects using a JSON parser, and when converted will be an NSArray containing two NSDictionarys.
You aren't going to be able to get your dictionary directly from a string of JSON. You are going to have to going to have to run it through a JSON parser first.
At this point, there is not one build into the iOS SDK, so you will have to download a third-party tool and include it in your project.
There are a number of different JSON parser, include TouchJSON, YAJL, etc. that you can find and compare. Personally, I am using JSONKit.
#MatthewGillingham suggests JSONKit. I imagine it does fine, but I've always used its competitor json-framework. No real reason, I just found it first and learned it first. I do think its interface is somewhat simpler, but plenty of people do fine with JSONKit too.
Using json-framework:
require JSON.h
...and then
NSString *myJsonString = #"[{'whatever': 'this contains'}, {'whatever', 'more content'}]";
NSArray *data = [myJsonString JSONValue];
foreach (NSDictionary *item in data) {
NSString *val = [item objectForKey:#"whatever"];
//val will contain "this contains" on the first time through
//this loop, then "more content" the second time.
}
If you have array of dictionary just assign objects in array to dictionary like
NSDictionary *dictionary = [array objectAtIndes:0];
and then use this dictionary to get values.
Related
I made one JSON string from the NSDictionary. The JSON string which I created doesn't come present the items in the order I entered keys and value pair in the NSDictionary .
Now I need all keys and value pairs returned as JSON string in alphabetic order. I tried lot of ways but not getting sorting of JSON string in alphabetic order.
Here's an example of the way the final string is being presented:
{
"SubscriberID" : "603",
"Amount" : "1",
"MerchantID" : "100012",
"Channel" : "Wallet",
"RequestCode" : "0331",
"PosID" : "0465F35F5577CUST",
"TID" : "0000014",
"Stan" : "NA"
}
How do I ensure the items are presented the way I entered them? Or how can I specify the items are alphabetically sorted?
SBJson is able to do this, set sortKeys to YES on SBJsonWriter
http://superloopy.io/json-framework/
SBJsonWriter *writer = [[SBJsonWriter alloc] init];
writer.sortKeys = YES;
// Turn on humanReadable if you also need it pretty-printed
// writer.humanReadable = YES;
NSData *result = [writer dataWithObject:myDictionary];
Like many key-value storage classes, NSDictionary does not guarantee order of the elements you've added. It is a mistake to assume that the key/value pairs, or keyset, will be returned with any particular order.
Further, JSON objects are unordered in the same fashion. You should not care about the order in which the objects are added. Nor should you (or your recipient) rely on being provided a JSON object with 'sorted' keys, as that's not really a valid concept with these particular structures. While ordering the keys might result in an iterator traversing the keys in the order you expect, it's not a guarantee, and should not be relied on.
I think you should revisit why you need the keys sorted in the first place, and see if you can find a way to avoid a dependency on their alphabetical ordering.
Edit: You mention the server requires an SHA hash of the JSON string. If you must, you can create a sorted JSON string by sorting the keys in an NSMutableArray, then creating the JSON string from those keys.
NSMutableArray *sortedKeys = [NSMutableArray arrayWithArray:[myDict allKeys]];
[sortedKeys sortedArrayUsingSelector:#selector(caseInsensitiveCompare:)];
NSMutableString *jsonString = [[NSMutableString alloc] init];
[jsonString appendString:#"{"];
for (NSString *key in sortedKeys) {
[jsonString appendFormat:#"\"%#\"", key];
[jsonString appendString:#":"];
[jsonString appendFormat:#"\"%#\"", [myDict objectForKey:key]];
[jsonString appendString:#","];
}
if ([jsonString length] > 2) {
[jsonString deleteCharactersInRange:NSMakeRange([jsonString length] - 1, 1)];
}
[jsonString appendString:#"}"];
This code hasn't been tested, so you might need to play with it a bit. Thought it would be much better if you could find a JSON library to do this for you, although you might not have as much control over the key ordering.
You can't do it (or at least you can't rely on that). JSON objects are unordered sets as you can read on JSON.org.
Actually,the system method [NSString stringWithFormat:] is what you need.So here is the easy way:
NSDictionary* inputDictionary = #{
#"SubscriberID" : #"603",
#"Amount" : #"1",
#"MerchantID" : #"100012",
#"Channel" : #"Wallet",
#"RequestCode" : #"0331",
#"PosID" : #"0465F35F5577CUST",
#"TID" : #"0000014",
#"Stan" : #"NA"
};
NSString* sortedJsonStr = [NSString stringWithFormat:#"%#", inputDictionary];
NSLog(#"sorted json string is %#", sortedJsonStr);
The result is:
{
Amount = 1;
Channel = Wallet;
MerchantID = 100012;
PosID = 0465F35F5577CUST;
RequestCode = 0331;
Stan = NA;
SubscriberID = 603;
TID = 0000014;
}
The question does not make sense, and therefore cannot be answered in its current form.
If you encode some JSON as {"keyB":"valueB","keyA":"valueA"}, take it's checksum, and then transmit the encoded JSON and the checksum to the remote site, the remote site has little choice but to take the checksum of the JSON as received and compare that. To do the checksum on sorted values it would have to decode the received JSON string into an NSDictionary, re-encode into "sorted" JSON, and then take the checksum of the reconstituted JSON, and that would be a lot of extra effort for no reason.
Far more likely is that there is some difference in either the way the checksum is being computed (padding of the SHA256 input, eg) or some difference in the JSON strings being used -- code page differences, escaped characters, one end is doing it on Base64 and the other not, etc.
im currently trying to parse some json data on the iphone.
I have been trawling the web for examples, but none seem to suit my purpose, i am using SBJson.
What I want is to be able to get an NSArray of Titles, Artisits, Status, etc. so that I can display them on a table view. Any help would be great, so far all i get is an array of "Values".
JSON = {"values":
[
{"Status":"N", "Filename":"RD207T04", "Title":"Simple Man (Explicit)", "Artist":"DIAFRIX F/DANIEL MERRIWE", "Release":"May11"},
{"Status":"N", "Filename":"CR221T27", "Title":"Midnight City", "Artist":"M83", "Release":"Dec11"},
{"Status":"N", "Filename":"ED211T03", "Title":"I\"ll Be Your Man", "Artist":"JAMES BLUNT", "Release":"Jul11"}
]}
You don't want an array of titles, artists, etc. You want the array of NSDictionarys represented by the values key. Then you can do:
cell.textLabel.text = [[valuesArray objectAtIndex:indexPath.row]valueForKey:#"Title"]];
inside your cellForRowAtIndexPath: delegate method. If you do not have this already, this is how to get that array:
NSArray *valuesArray = [[myJsonString JSONValue]objectForKey:#"values"];
Thanks mate, I was definately over complicating things:
The end code was this:
NSArray *valuesArray = [[playlist JSONValue] objectForKey:#"values"];
NSString *test = [[valuesArray objectAtIndex:0]valueForKey:#"Title"];
NSLog(#"test = %#", test);
Now all I have to do is iterate through the set :)
I have one genuine question which I am facing at this point and I am sure someone might be able to help me.
I have a JSON Post which looks like:
{
"CustomerAccount":{
"CustomerUID":"String content",
"UserName":"String content",
"Password":"String content",
"OldPassword":"String content",
"Email":"String content",
"QuestionUID":2147483647,
"QuestionAnswer":"String content",
"EAlerts":true
}
}
Now I have a dictionay which set's value of CustomerUID, UserName, etc.. Now if I want to bind a upper level to bind all that to CustomerAccount and send as my JSONRepresentation, is there any easier way than actually creating a new dictionary and setting a value of key "CustomerAccount" in this example? I am sure there might be a better way of doing that.
Thanks.
Not entirely sure I follow, but is this what you want maybe:
NSDictionary *dictA = <dictionary_with_customeruid_etc>;
NSDictionary *customerAccountDict = [NSDictionary dictionaryWithObjectsAndKeys:dictA, #"CustomerAccount", nil];
But I'm not sure I follow your question entirely so maybe you want something else. Please let us know a bit more about what you're trying to do.
I don't really understand your question but ill give it a try.
You can easily parse the JSON string to a NSDictionary using JSONKit https://github.com/johnezang/JSONKit
JSONKit is a very fast and lightweight library and you can parse the string and get the wanted value like this:
NSDictionary *dict = [jsonString objectFromJSONString];
NSString *value = [dict valueForKey:#"key"];
To actually set a value in your JSON string you should use rangeOfString: .location to get the range if the existing value then replaceOccurenciesOfString:[jsonString substringWithRange:NSMakeRange(loc,len)] withString:VALUE.
I am building an app that uses a UPC data base API. I am getting back a JSON object, example from here: http://www.simpleupc.com/api/methods/FetchNutritionFactsByUPC.php
{
"success":true,
"usedExternal":false,
"result"
{
"calories_per_serving":"150",
"cholesterol_per_serving":"15",
"cholesterol_uom":"Mg",
"dvp_calcium":"30",
"dvp_cholesterol":"4",
"dvp_iron":"2",
"dvp_protein":"17",
"dvp_saturated_fat":"8",
"dvp_sodium":"10",
"dvp_total_fat":"4",
"dvp_vitamin_a":"10","
"dvp_vitamin_c":"0",
"dvp_vitamin_d":"25",
"fat_calories_per_serving":"25",
"fiber_per_serving":"<1",
"fiber_uom":"G",
"ingredients":"Fat Free Milk, Milk, Sugar, Cocoa (Processed With Alkali),
Salt, Carrageenan, Vanillin (Artificial Flavor),
Lactase Enzyme, Vitamin A Palmitate And Vitamin D3.",
"protein_per_serving":"8",
"protein_uom":"G",
"size":"240",
"units":"mL",
"servings_per_container":"8",
"sodium_per_serving":"230",
"sodium_uom":"Mg",
"total_fat_per_serving":"2.5",
"total_fat_uom":"G",
"trans_fat_per_serving":"0",
"trans_fat_uom":"G",
"upc":"041383096013"
}
}
My problem is with parsing the "ingredients" element, which is a sub list of the object dictionary.
How would you suggest parsing the ingredients list? If I could get it to an NSArray, assuming commas are separators, that would have been great.
I tried to do this, but looks like its just a string, so no way to parse it.
Any suggestion would be more than welcome. Thanks!
//Thats the whole JSON object
NSDictionary *json_dict = [theResponseString JSONValue];
//Getting "results" which has all the product info
NSArray *myArray = [[NSArray alloc] init];
myArray = [json_dict valueForKey:#"result"];
Now how do I get "ingredients" from myArray in an array form?
You're getting result as an array, but (in JSON terminology) it's not an array. It's an object, so use an NSDictionary. Something like this:1
NSDictionary *result = [json_dict objectForKey:#"result"];
Then you can get the inner ingredients object from that:
NSString *ingredients = [result objectForKey:#"ingredients"];
Edited as per #Bavarious' comment.
1Apologies for glaring errors, as I'm not terribly well-versed in Objective-C. You might need to allocate memory for the returned NSDictionary and NSString pointers; I'm not sure.
Here's all you need to do:
NSDictionary *json_dict = [theResponseString JSONValue];
// Use a key path to access the nested element.
NSArray *myArray = [json_dict valueForKeyPath:#"result.ingredients"];
EDIT
Whoops, Matt's right. Here's how to deal with the string value:
// Use a key path to access the nested element.
NSString *s = [json_dict valueForKeyPath:#"result.ingredients"];
NSArray *ingredients = [s componentsSeparatedByString:#", "];
Note that you might need to trim the '.' character off the last element of the array.
I'm using the SBJSONParser for my iphone app. Up to now, i've been parsing simple json strings such as: ["Business1","Business2"]
I'm now using PHP to get both the business name and business ID from the database within the same json string, so my PHP is giving me a result like this:
{"business_1A" : "ABC_1","businees_2A": "ABC_2" }
Here's the code that i'm currently using to process the first JSON output which works fine:
businessNames is an NSMutableArray in the following code.
NSString *businessNamesJSON = [[NSString alloc]initWithContentsOfURL:[NSURL URLWithString:[NSString stringWithFormat:#"businessNamesJSON.php"]]];
SBJsonParser *parser = [[SBJsonParser alloc]init];
businessNames = [[parser objectWithString:businessNamesJSON error:nil]copy];
Basically, I want to split the second JSON output so that I can have two separate NSMutableArrays, one which contains the business Names and the other which holds the IDs.
How do I extract or split the second JSON output so I can do this?
Thanks in advance.
Hy there
Let me take a step back. Since you have a list of companies wouldn't it be a better way to represent your data with an array in json like so:
[
{
"identifier": "ABC_1",
"name": "business_1A"
},
{
"identifier": "ABC_2",
"name": "businees_2A"
}
]
I believe this would make the parsing of the data easier for you and it would allow you to add more attributes in the future.
So once you have this structure you can parse the json data and then loop over the entries and extract the values for the keys identifier and name (in this case) respectively.
{"business_1A" : "ABC_1","businees_2A": "ABC_2" } defined an object in JSON terms, which will be returned by any sane JSON parser as an NSDictionary in Objective-C, being a collection of mappings from one object to another.
You seem then to want all the keys and all the values separately. In that case you can just get them from the NSDictionary:
SBJsonParser *parser = [[SBJsonParser alloc] init];
businessNamesDictionary = [parser objectWithString:businessNamesJSON error:nil];
NSLog(#"names: %#", [businessNamesDictionary allKeys]);
NSLog(#"values: %#", [businessNamesDictionary allValues]);
Take mutableCopys if you want them. Use objectsForKeys:notFoundMarker: if you want to guarantee that the values come out in the same order as the keys — the order of each is explicitly undefined in the documentation so don't rely on whatever order you happen to get on whichever version of the OS you happen to test against.