Question

我试图理解我在使用sbjson解析调用Twitter的GET趋势返回的以下json时出现的问题/：woeid

我使用以下网址：@“http://api.twitter.com/1/trends/1.json”，我得到以下回复:(截断以节省空间）

[  
  {  
    "trends": [  
      {  
        "name": "Premios Juventud",  
        "url": "http://search.twitter.com/search?q=Premios+Juventud",  
        "query": "Premios+Juventud"  
      },  
      {  
        "name": "#agoodrelationship",  
        "url": "http://search.twitter.com/search?q=%23agoodrelationship",  
        "query": "%23agoodrelationship"  
      }  
    ],  
    "as_of": "2010-07-15T22:40:45Z",  
    "locations": [  
      {  
        "name": "Worldwide",  
        "woeid": 1  
      }  
    ]  
  }  
]

以下是我用于解析和显示名称和网址的代码：

NSMutableString *content = [[NSMutableString alloc] initWithBytes:[responseData bytes] length:[responseData length] encoding:NSUTF8StringEncoding];

[content replaceCharactersInRange:NSMakeRange(0, 1) withString:@""];
[content replaceCharactersInRange:NSMakeRange([content length]-1, 1) withString:@""];
NSLog(@"Content is: %@", content);

SBJsonParser *parser = [[SBJsonParser alloc] init];
NSDictionary *json = [parser objectWithString:content];


//NSArray *trends = [json objectForKey:@"trends"];
NSArray *trends = [json objectForKey:@"trends"];
for (NSDictionary *trend in trends)
{
    [viewController.names addObject:[trend objectForKey:@"name"]];
    [viewController.urls addObject:[trend objectForKey:@"url"]];
}

[parser release];

这是示例代码，因为它的目标是Twitter的GET趋势调用，现在已弃用。该代码仅在我手动删除第一个'['和last']'时才有效。但是，如果我不从响应中删除这些字符，解析器将返回一个 NSString元素的NSArray：json响应。

我应该如何正确解析此响应。提前谢谢。

Answer 1

我自己解决了这个问题，我很惊讶NSArray回来时只有一个看似是字符串的元素。

数组中的一个元素不是NSString而是NSDictionary，一旦我理解了这一点，我可以通过将元素分配给NSDictionary来正确处理数据，然后使用适当的密钥访问“趋势”数据：

NSMutableString *content = [[NSMutableString alloc] initWithBytes:[responseData bytes] length:[responseData length] encoding:NSUTF8StringEncoding];

SBJsonParser *parser = [[SBJsonParser alloc] init];
NSArray *json = [parser objectWithString:content];

NSDictionary *trends = [json objectAtIndex:0];
for (NSDictionary *trend in [trends objectForKey:@"trends"])
{
    [viewController.names addObject:[trend objectForKey:@"name"]];
    [viewController.urls addObject:[trend objectForKey:@"url"]];
}

[parser release];

使用Apple提供的新发布的NSJSONSerialization更清晰：

- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{ 
    NSArray *json = [NSJSONSerialization JSONObjectWithData:responseData options:0 error:nil];    

    NSDictionary *trends = [json objectAtIndex:0];
    for (NSDictionary *trend in [trends objectForKey:@"trends"])
    {
        [viewController.names addObject:[trend objectForKey:@"name"]];
        [viewController.urls addObject:[trend objectForKey:@"url"]];
    }    

    [UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
    [viewController.serviceView reloadData];
}

SBJSON解析Twitter的GET趋势问题/：woeid

1 个答案: