Convert Swift method using extend and append functions to Objective-C - ios

Question

I have this Swift method that I want to convert to Objective-C. The method is using the extend method of Array and as far as I understand it just adds an object to the array while calling itself again.
Swift:
///the method to serialized all the objects
func serializeObject(object: AnyObject,key: String?) -> Array<HTTPPair> {
var collect = Array<HTTPPair>()
if let array = object as? Array<AnyObject> {
for nestedValue : AnyObject in array {
collect.extend(self.serializeObject(nestedValue,key: "\(key!)[]"))
}
} else if let dict = object as? Dictionary<String,AnyObject> {
for (nestedKey, nestedObject: AnyObject) in dict {
var newKey = key != nil ? "\(key!)[\(nestedKey)]" : nestedKey
collect.extend(self.serializeObject(nestedObject,key: newKey))
}
} else {
collect.append(HTTPPair(value: object, key: key))
}
return collect
}
What I've done so far in Objective-C.
- (NSArray*) serializeObject:(id)obj key:(NSString*)key
{
NSMutableArray* collect = [NSMutableArray array];
if ([obj isKindOfClass:[NSArray class]])
{
NSArray* objArray = obj;
if (obj)
{
for (id nestedObj in objArray)
{
[collect addObject:[self serializeObject:nestedObj key:[NSString stringWithFormat:#"%#[]", key]]];
}
}
}
else if ([obj isKindOfClass:[NSDictionary class]])
{
NSDictionary* dict = obj;
if (dict)
{
for (NSString* nestedKey in dict)
{
NSString* newKey = key != nil ? [NSString stringWithFormat:#"%#[%#]", key, nestedKey] : nestedKey;
id nestedObject = [dict objectForKey:newKey];
if (nestedObject)
{
[collect addObject:[self serializeObject:nestedObject key:newKey]];
}
}
}
}
else
{
[collect addObject:[[WEEHTTPPair alloc] initWithValue:obj andKey:key]];
}
return collect;
}
The goal is to get an NSArray of WEEHTTPPair objects for every key/value pair in the dictionary but I lose the meaning of extend and append to apply in my Objective-C code. For me it looks like both are adding the object to the array which is created new anyway but it's more that I lack in knowledge so far.
[EDIT]
The method is used accordingly.
Swift.
///convert the parameter dict to its HTTP string representation
func stringFromParameters(parameters: Dictionary<String,AnyObject>) -> String {
return join("&", map(serializeObject(parameters, key: nil), {(pair) in
return pair.stringValue()
}))
}
I converted to Objective-C borrowed BlockKits map extension.
Objective-C.
- (NSString*) stringFromParameters:(NSDictionary*)parameters
{
WEENSArrayBlocksKit* blockKit = [WEENSArrayBlocksKit new];
NSArray* serializedParams = [self serializeObject:parameters key:nil];
NSArray* arrayParams = [blockKit bk_map:serializedParams withBlock:^id(id obj)
{
// obj is an array without the desired results
WEEHTTPPair* httpPair = obj;
NSString* stringValue = nil;
if (httpPair)
{
stringValue = [httpPair stringValue];
}
return stringValue;
}];
NSString* joinedString = [arrayParams componentsJoinedByString:#"&"];
return joinedString;
}

Answer 1

When you do this:
[collect addObject:[self serializeObject:nestedObject key:newKey]];
You are adding an NSArray to your collect object. Instead, you want to add the objects contained within the response to collect:
[collect addObjectsFromArray:[self serializeObject:nestedObject key:newKey]];