creating a nested json object with objective-c - objective-c

Question

I have below snippet that I am supposed to create in objective-c.
{
"expression": "???=n1+n2+n3+n4",
"terms": [
{
"name": "termsTitle",
"term": [
{
"name": "answer",
"value": "???"
}
]
}
]
}
Here's my attempt to create it
NSMutableArray *terms= [[NSMutableArray alloc] init];
NSArray *keysTerms = [[NSArray alloc] initWithObjects:#"name", #"term", nil];
NSMutableArray *term= [[NSMutableArray alloc] init];
NSArray *objectsTerms = [[NSArray alloc] initWithObjects:#"answer",term, nil];
NSDictionary *termsDict = [[NSMutableDictionary alloc] initWithObjects:objectsTerms forKeys:keysTerms];
[terms addObject:termsDict];
NSDictionary *statement = [[NSDictionary alloc]
initWithObjectsAndKeys:expression,#"expression",
terms,#"terms",
nil];
I think I am close but for some reason, this is not working for me. I would appreciate any help. Thanks in advance.

Answer 1

this should work
NSDictionary* termDict = [NSDictionary dictionaryWithObjects:#[#"answer",#"???"] forKeys:#[#"name",#"value"]];
NSArray* termArray = [NSArray arrayWithObjects:termDict, nil];
NSDictionary* termsDict = [NSDictionary dictionaryWithObjects:#[#"termsTitle",termArray] forKeys:#[#"name",#"term"]];
NSMutableArray* terms = [NSMutableArray arrayWithObjects:termsDict, nil];
NSDictionary* result = [NSDictionary dictionaryWithObjects:#[#"???=n1+n2+n3+n4",terms] forKeys:#[#"expression",#"terms"]];
NSLog(#"result: %#",[result description]);
The Result
2014-11-21 15:03:14.396 Answering_question[23716:113224] result: {
expression = "???=n1+n2+n3+n4";
terms = (
{
name = termsTitle;
term = (
{
name = answer;
value = "???";
}
);
}
);
}

Answer 2

If you have some problems with the structure you need to write more detailed code. Like this:
NSMutableDictionary *mainDict= [NSMutableDictionary new];
[mainDict setObject:#"???=n1+n2+n3+n4" forKey:#"expression"];
NSMutableArray *terms = [NSMutableArray new];
NSMutableDictionary *term = [NSMutableDictionary new];
[term setObject:#"name" forKey:#"termsTitle"];
NSMutableArray *subTerms = [NSMutableArray new];
NSMutableDictionary *subTerm = [NSMutableDictionary new];
[subTerm setObject:#"answer" forKey:#"name"];
[subTerm setObject:#"???" forKey:#"value"];
[subTerms addObject:subTerm];
[term setObject:subTerms forKey:#"term"];
[terms addObject:term];
[mainDict setObject:terms forKey:#"terms"];
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:mainDict
options:NSJSONWritingPrettyPrinted
error:nil];
NSString *jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
Output:
{
"expression" : "???=n1+n2+n3+n4",
"terms" : [
{
"termsTitle" : "name",
"term" : [
{
"name" : "answer",
"value" : "???"
}
]
}
]
}