将 Json 解析为提供 "null" 值的对象

Question

无法将此 json 数据解析为对象。我用其他 URL 尝试过相同的代码，工作正常。请指出我哪里做错了？

-(void)callAPI{
    NSData *data=[NSData dataWithContentsOfURL:[NSURL URLWithString:@"https:s.json"]];
    NSError *error=nil;
    id response=[NSJSONSerialization JSONObjectWithData:data options:
                 NSJSONReadingMutableContainers | NSJSONReadingMutableLeaves error:&error];

    if (error) {
        NSLog(@"%@",[error localizedDescription]);
    } else {

        NSLog(@"%@",response);}}

输出无法读取数据，因为它的格式不正确。

Answer 1

我为你的问题找到了非常完美的解决方案，效果很好now.Please检查下面的答案

- (void)callAPI 
{

  NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init];
  [request setHTTPMethod:@"GET"];
  [request setURL:[NSURL URLWithString:@"https://dl.dropboxusercontent.com/s/2iodh4vg0eortkl/facts.json"]];
  [[[NSURLSession sharedSession] dataTaskWithRequest:request completionHandler:
  ^(NSData * data,
    NSURLResponse * response,
    NSError * error) {
      NSString *jsonString = [[NSString alloc] initWithData:data encoding:NSASCIIStringEncoding];
      NSLog(@"jsonString is: %@", jsonString);
      NSData *dataCon = [jsonString dataUsingEncoding:NSUTF8StringEncoding];
      id jsonVal = [NSJSONSerialization JSONObjectWithData:dataCon options:0 error:nil];
      if([jsonVal isKindOfClass:[NSDictionary class]]) {
          NSLog(@"The response starts with NSDictionary");
          NSArray *arrJsonVal = [jsonVal objectForKey:@"rows"];
          NSMutableArray *arrTitle = [[NSMutableArray alloc]init];
          NSMutableArray *arrDesc = [[NSMutableArray alloc]init];
          NSMutableArray *arrImage = [[NSMutableArray alloc]init];
          for(NSDictionary *dict in arrJsonVal) {
              NSString *strTitle = [dict objectForKey:@"title"];
              NSString *strDesc = [dict objectForKey:@"description"];
              NSString *strImage = [dict objectForKey:@"imageHref"];

              [arrTitle addObject:strTitle];
              [arrDesc addObject:strDesc];
              [arrImage addObject:strImage];
          }
          NSLog(@"arrTitle is - %@",arrTitle);
          NSLog(@"arrDesc is - %@",arrDesc);
          NSLog(@"arrImage is - %@",arrImage);

      }else {
          NSLog(@"The response starts with NSArray");
      }
  }] resume];

}

打印结果为

之后

则数组结果为

终于有结果了

将 Json 解析为提供 "null" 值的对象

Parsing Json to object giving "null" Value

objective-c

nsjsonserialization