Question

I am new to json and confuse how to do this. I have this basic info below i need to convert

    "trailer":
         "window":"broken"
         "sidesteps":"dent"
    "tractor":
        "window":"craked"
        "sidesteps":"missing"
     "tire":
        "tire1":
            "pressure":"120"
            "rim":"good"
         "tire2":
            "pressure":"120"
            "rim":"good"

Answer 1

Create a dictionary from all the values you fetched from textFields. It will look like this,

NSDictionary *dictionary = @{@"trailer":@{@"window":@"broken", @"sidesteps":@"missing", @"tractor": @{@"window":@"broken",@"sidesteps":@"missing"}, @"tire":@{@"tire1" : @{@"pressure" : @"120", @"rim":@"good"}}}};

Output:

dictionary =   {
        "trailer": {
            "window": "broken",
            "sidesteps": "missing",
            "tractor": {
                "window": "broken",
                "sidesteps": "missing"
            },
            "tire": {
                "tire1": {
                    "pressure": "120",
                    "rim": "good"
                }
            }
        }
    }

You can use NSMutableDictionary to create a similar structure dynamically. You can create multiple mutable dictionaries and add it as an object of another dictionary to achieve the above result.

To convert to JSON data you can do this,

NSError *error;
NSData *postData = [NSJSONSerialization dataWithJSONObject:dictionary options:NSJSONWritingPrettyPrinted error:&error];

If you want to convert to a string to view the data,

NSString *jsonString = [[NSString alloc] initWithData:postData encoding:NSStringEncodingConversionAllowLossy];
NSLog(@"jsonString = %@", jsonString);

If you want to set this postbody to http request and pass it to server, you can set it as,

[urlRequest setHTTPBody:postData];