Question

Here is the simplified JSON file, I need to download it from a net service and parse results in a table!

EDIT: I provide now more precise code, cleaned and formatted by online tool:

{
  "main": [
    {
      "id": 0, <--- float value
      "type": "type0", <--- STRING value
      "valueA": {
        "valueA1": 1, <--- float value
        "valueA2": 2, <--- float value
        "valueA3": 3  <--- float value
      },
      "valueB": {
        "valueB1": 1, <--- float value
        "valueB2": 2  <--- float value
      },
      "valueC": [
        {
          "valueC1": "string0C1", <--- STRING value
          "valueC2": 2, <--- float value
          "valueC3": 3, <--- float value
        }
      ]
    },

FORMATTED by online tool jsonviewer.stack.hu:

I need to parse it with AFJSONRequestOperation, and I write this code:

NSMutableArray *main = [JSON objectForKey:@"main"];
arrayID = [main valueForKey:@"id"];
arrayType = [main valueForKey:@"type"];

NSMutableArray *arrayValueC = [main valueForKey:@"valueC"];
NSMutableString *stringC1 = [arrayValueC valueForKey:@"valueC1"]; 

// I CANT USE objectForKey, XCode give an exception -[__NSArrayI objectForKey:]: unrecognized selector sent to instance

NSLog(@"id: %@",arrayID);
NSLog(@"type: %@",arrayType);
NSLog(@"string: %@",stringC1);

When I parse, I get this results from NSLog:

id: (
    0,
    1,
    2,
    3,
    4,
    5,
    6,
    7,
    8,
    9
)

type: (
    type0,
    type1,
    type2,
    type3,
    type4,
    type5,
    type6,
    type7,
    type8,
    type9
)

string: (
        (
        "string0C1"
    ),
        (
        "string2C1"
    ),
        (
        "string2C1"
    ),
        (
        "string3C1"
    ),
        (
        "string4C1"
    ),
        (
        "string5C1"
    ),
        (
        "string6C1"
    ),
        (
        "string7C1"
    ),
        (
        "string8C1"
    ),
        (
        "string9C1"
    )
)

As u can see its all perfect, I can extrapolate every value of ID (float) and TYPE (string), but I hate the round brackets in every object of the valueC1 string: how can I get the clean valueC1 without brackets and quotation marks? Please if u can provide some code. Thanks!

Answer 1

Don’t use valueForKey:. Use objectForKey: instead. This is probably the major problem. But once you use it, you might run into new problem:

The following contains a problem that will manifest itself when arrayValueA is accessed the first time:

NSMutableArray *arrayValueA = [arrayMain objectForKey:@"valueA"];

The element stored at valueA is an object i.e. a dictionary and not an array.

Finally, your simplified JSON is invalid anyway. Several values are missing double quotes, e.g.:

"id": id0

should be:

"id": "id0"

You better shows the real JSON data and the real code.

Update:

You should be able to access the JSON data with the following code:

NSArray *main = [JSON objectForKey:@"main"];
NSDictionary* main0 = [main objectAtIndex:0];
arrayID = [main0 objectForKey:@"id"];
arrayType = [main0 objectForKey:@"type"];

NSArray *arrayValueC = [main objectForKey:@"valueC"];
NSDictionary *elem0 = [arrayValueC objectAtIndex:0];
NSString *stringC1 = [arrayValueC objectForKey:@"valueC1"]; 

NSLog(@"id: %@",arrayID);
NSLog(@"type: %@",arrayType);
NSLog(@"string: %@",stringC1);