Objective-C how to convert nsdata from web service to nsarray - objective-c

Question

How do i convert id to an array?
I have an apple app that talks to a server.
Issue i have is the app returns the data in the form of id however i need to convert this to an array as the actual returned data looks like the following.
[["30","2",1],["15","67",1],["30","4",1]]
It is actually the output from a mysql server
The actual app code looks like the following
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:#"blah blah"]];
NSURL_Layer * connection = [[NSURL_Layer alloc]initWithRequest:request];
[connection setCompletitionBlock:^(id obj, NSError *err) {
if (!err) {
//Need to convert the id to nsarray here, dunno how
} else {
//There was an error
}
}];
[connection start];
The NSURL.h
-(id)initWithRequest:(NSURLRequest *)req;
#property (nonatomic,copy)NSURLConnection * internalConnection;
#property (nonatomic,copy)NSURLRequest *request;
#property (nonatomic,copy)void (^completitionBlock) (id obj, NSError * err);
-(void)start;
NSURL.m
-(id)initWithRequest:(NSURLRequest *)req {
self = [super init];
if (self) {
[self setRequest:req];
}
return self;
}
-(void)start {
container = [[NSMutableData alloc]init];
internalConnection = [[NSURLConnection alloc]initWithRequest:[self request] delegate:self startImmediately:YES];
if(!sharedConnectionList)
sharedConnectionList = [[NSMutableArray alloc] init];
[sharedConnectionList addObject:self];
}
-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
[container appendData:data];
}
//If finish, return the data and the error nil
-(void)connectionDidFinishLoading:(NSURLConnection *)connection {
if([self completitionBlock])
[self completitionBlock](container,nil);
[sharedConnectionList removeObject:self];
}
//If fail, return nil and an error
-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
if([self completitionBlock])
[self completitionBlock](nil,error);
[sharedConnectionList removeObject:self];
}
Update:
i have added
NSURL_Layer * connection = [[NSURL_Layer alloc]initWithRequest:request];
[connection setCompletitionBlock:^(id obj, NSError *err) {
if (!err) {
NSError* error;
NSArray* array = [NSJSONSerialization JSONObjectWithData:obj options:NSJSONReadingAllowFragments error:&error];
} else {
//There was an error
}
}];
[connection start];
but returns error
error NSError * domain: #"NSCocoaErrorDomain" - code: 3840
_userInfo NSDictionary * 1 key/value pair
[0] (null) #"NSDebugDescription" : #"Invalid value around character 0."
Update: I put
NSLog(#"Data as string:%#", [[NSString alloc]initWithData:obj encoding:NSUTF8StringEncoding]);
which gave me a strange feedback. As a result i looked at my url request full code is below.
NSString *post = [NSString stringWithFormat:#"unique_id=%#&unique_password=%#",ServerUniqueID,ServerPassword];
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
NSString *postLength = [NSString stringWithFormat:#"%lu", (unsigned long)[post length]];
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:#"blah blah"]];
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setHTTPBody:postData];
NSURL_Layer * connection = [[NSURL_Layer alloc]initWithRequest:request];
[connection setCompletitionBlock:^(id obj, NSError *err) {
if (!err)
{
NSError* error;
NSArray* array = [NSJSONSerialization JSONObjectWithData:[NSData dataWithData: obj] options:NSJSONReadingAllowFragments error:&error];
NSLog(#"Data as string:%#", [[NSString alloc]initWithData:obj encoding:NSUTF8StringEncoding]);
int temp = array.count;
}
else
{
//There was an error
}
}];
[connection start];
if i remove
[request setHTTPMethod:#"POST"];
[request setValue:postLength forHTTPHeaderField:#"Content-Length"];
[request setHTTPBody:postData];
it works
if its in it dosn't so i have a whole new issue to look into.

Answer 1

you save the bytes into a container variable, alas the id infact NSData
(note id is just a 'wildcard pointer' that means ANY objC object)
so your id is NSData and from what you show it seems to be 3 json arrays... but no real JSON... (["30","2",1]["15","67",1]["30","4",1] isn't anything)
EITHER make the server send you JSON and THAT you can parse into a dictionary/array using NSJSONSerialization
OR write a custom separator to convert the data