gistfile1.m

/*
    Got data from the web service
*/
- (void)requestFinished:(ASIHTTPRequest *)request {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
    // Use when fetching text data
    NSString *responseString = [request responseString];
    
    // parse the response
    SBJsonParser *parser = [SBJsonParser new];
    id content = [responseString JSONValue];
    if(!content){
        // parsing error
        NSLog(@"%@", parser.errorTrace);
        return;
    }
    
    /*
      In my case, the data takes the form of an array of dictionarys:
        [{...},{...}]

      So content is an NSArray (or acts like one) and each node in there
      is (or acts like) an NSDictionary. So I can run commands like this on
      my parsed data:

      [content count]; // how many items
      // get the value for key in the 1st object
      [[content objectAtIndex:0] objectForKey:@"key"];
    */
    
    [pool release];
}

/*
    The async request to get new data failed
*/
- (void)requestFailed:(ASIHTTPRequest *)request {
    NSError *error = [request error];
    NSLog(@"%@", error);
}