JSON Parsing in iOS 7

Question

I am creating an app for as existing website. They currently has the JSON in the following format :

[

   {
       "id": "value",
       "array": "[{\"id\" : \"value\"} , {\"id\" : \"value\"}]"
   },
   {
       "id": "value",
       "array": "[{\"id\" : \"value\"},{\"id\" : \"value\"}]"
   } 
]

which they parse after escaping the \ character using Javascript.

My problem is when i parse it in iOS using the following command :

NSArray *result = [NSJSONSerialization JSONObjectWithData:jsonData options:kNilOptions error:&localError];

and do this :

NSArray *Array = [result valueForKey:@"array"];

Instead of an Array I got NSMutableString object.

• The website is already in production so I just cant ask them to change their existing structure to return a proper JSON object. It would be a lot of work for them.

• So, until they change the underlying stucture, is there any way i can make it work in iOS like they do with javascript on their website?

Any help/suggestion would be very helpful to me.

Answer 1

The correct JSON should presumably look something like:

[
    {
        "id": "value",
        "array": [{"id": "value"},{"id": "value"}]
    },
    {
        "id": "value",
        "array": [{"id": "value"},{"id": "value"}]
    }
]

But, if you're stuck this the format provided in your question, you need to make the dictionary mutable with NSJSONReadingMutableContainers and then call NSJSONSerialization again for each of those array entries:

NSMutableArray *array = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:&error];
if (error)
    NSLog(@"JSONObjectWithData error: %@", error);

for (NSMutableDictionary *dictionary in array)
{
    NSString *arrayString = dictionary[@"array"];
    if (arrayString)
    {
        NSData *data = [arrayString dataUsingEncoding:NSUTF8StringEncoding];
        NSError *error = nil;
        dictionary[@"array"] = [NSJSONSerialization JSONObjectWithData:data options:0 error:&error];
        if (error)
            NSLog(@"JSONObjectWithData for array error: %@", error);
    }
}

Answer 2

//-------------- get data url--------

NSURLRequest *request=[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://echo.jsontest.com/key/value"]];

NSData *data=[NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
NSLog(@"response==%@",response);
NSLog(@"error==%@",Error);
NSError *error;

id jsonobject=[NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:&error];

if ([jsonobject isKindOfClass:[NSDictionary class]]) {
    NSDictionary *dict=(NSDictionary *)jsonobject;
    NSLog(@"dict==%@",dict);
}
else
{
    NSArray *array=(NSArray *)jsonobject;
    NSLog(@"array==%@",array);
}

Answer 3

// ----------------- json for localfile---------------------------

NSString *pathofjson = [[NSBundle mainBundle]pathForResource:@"test1" ofType:@"json"];
NSData *dataforjson = [[NSData alloc]initWithContentsOfFile:pathofjson];
arrayforjson = [NSJSONSerialization JSONObjectWithData:dataforjson options:NSJSONReadingMutableContainers error:nil];
[tableview reloadData];

//------------- json for urlfile-----------------------------------

NSString *urlstrng = @"http://www.json-generator.com/api/json/get/ctILPMfuPS?indent=4";
NSURL *urlname = [NSURL URLWithString:urlstrng];
NSURLRequest *rqsturl = [NSURLRequest requestWithURL:urlname];

//------------ json for urlfile by asynchronous----------------------

[NSURLConnection sendAsynchronousRequest:rqsturl queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
    arrayforjson = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
    [tableview reloadData];
}];

//------------- json for urlfile by synchronous----------------------

NSError *error;
NSData *data = [NSURLConnection sendSynchronousRequest:rqsturl returningResponse:nil error:&error];

 arrayforjson = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:&error];

[tableview reloadData];
} ;

Answer 4

• You may always unescape the jsonData before deliver it to NSJSONSerialization. Or you may use the string got to construct another json object to get the array.

• NSJSONSerialization is doing right, the value in your example should be a string.

Answer 5

NSString *post=[[NSString stringWithFormat:@"command=%@&username=%@&password=%@",@"login",@"username",@"password"]stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

    NSMutableURLRequest *request=[NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://www.blablabla.com"]];

   [request setHTTPMethod:@"POST"];

   [request setValue:@"x-www-form-urlencoded" forHTTPHeaderField:@"content-type"];
    [request setHTTPBody:[NSData dataWithBytes:[post UTF8String] length:strlen([post UTF8String])]];

   NSData *data=[NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];

    id jsonobject=[NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];

    if ([jsonobject isKindOfClass:[NSDictionary class]])
    {

        NSDictionary *dict=(NSDictionary *)jsonobject;
        NSLog(@"dict==%@",dict);

    }
    else
    {

        NSArray *array=(NSArray *)jsonobject;
        NSLog(@"array==%@",array);
    }

Answer 6

As another answer has said, that value is a string.

You can get around it by turning that string into data, as it seems to be a valid json string and then parse that json data object back into an array which you can add to your dictionary as the value for the key.