与iOS JSON问题6

Question

我试图分析JSON它看起来像这样：

[{"category": "anti-social-behaviour", "persistent_id": "", "location_subtype": "", "id": 23193805, "location": {"latitude": "52.6387452", "street": {"id": 883166, "name": "On or near Charnwood Street"}, "longitude": "-1.1136914"}, "context": "", "month": "2013-04", "location_type": "Force", "outcome_status": null}, 
{"category": "anti-social-behaviour", "persistent_id": "", "location_subtype": "", "id": 23195135, "location": {"latitude": "52.6288245", "street": {"id": 883098, "name": "On or near Roslyn Street"}, "longitude": "-1.1106710"}, "context": "", "month": "2013-04", "location_type": "Force", "outcome_status": null},' 

我想用这种方式来分析它：

NSString *url = @"http://data.police.uk/api/crimes-at-location?date=2012-02&location_id=12345"; 

NSData *jsonDataString = [[NSString stringWithContentsOfURL:[NSURL URLWithString:url] encoding:NSUTF8StringEncoding error: nil] dataUsingEncoding:NSUTF8StringEncoding]; 

NSError *error = nil; 

NSDictionary *results = [NSJSONSerialization JSONObjectWithData:jsonDataString options:NSJSONReadingMutableContainers | NSJSONReadingMutableLeaves error:&error]; 

NSArray *myResults = [results valueForKeyPath:@""]; 

NSDictionary *bug = (NSDictionary *)[myResults objectAtIndex:0]; 

// And get its name 
NSString *bugName = [bug objectForKey:@"category"]; 
NSLog(@"%@",bugName); 

我得到错误：__NSArrayI objectAtIndex ：]：索引0超出空阵列的边界'

那么我应该把valueForKeyPath放在哪里？

在此先感谢

Answer 1

唉...

NSData *jsonDataString = [[NSString stringWithContentsOfURL:[NSURL URLWithString:url] encoding:NSUTF8StringEncoding error: nil] dataUsingEncoding:NSUTF8StringEncoding]; 

NSError *error = nil; 

NSArray* myResults = [NSJSONSerialization JSONObjectWithData:jsonDataString options:NSJSONReadingMutableContainers | NSJSONReadingMutableLeaves error:&error]; 

if (error != nil) { 
    NSLog(@"%@", error); 
} 

NSDictionary *bug = (NSDictionary *)[myResults objectAtIndex:0]; 

// And get its name 
NSString *bugName = [bug objectForKey:@"category"]; 
NSLog(@"%@",bugName);