iPhone 中的 NSDictionary 解析异常

Question

我正在使用这段代码，它给出了异常

    NSMutableArray *streams = (NSMutableArray *)[feed valueForKey:@"comments"];
    NSMutableArray *streams1 = (NSMutableArray *)[streams valueForKey:@"data"];
    //NSMutableArray *streams2 = (NSMutableArray *)[streams1 valueForKey:@"message"];
    // loop over all the stream objects and print their titles
    int index;
    NSMutableDictionary *stream;
  for (index = 0; index < [feed count];index++) {
        stream = (NSMutableDictionary *)[streams1 objectAtIndex:index];

                NSLog(@"Name of sender is: %@", [stream valueForKey:@"message"]); 

        }


FaceBookTable *detailViewController = [[FaceBookTable alloc] initWithNibName:@"FaceBookTable" bundle:nil];
    // ...
    // Pass the selected object to the new view controller.
    detailViewController.fbGraph = fbGraph;
    detailViewController.dummyArray  = [ feed valueForKey:@"message"];
    detailViewController.dict = stream;

}

异常是

-[__NSArrayI isEqualToString:]: unrecognized selector sent to instance 0x5dae960
2011-06-15 16:14:07.835 MultiSocial[8042:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayI isEqualToString:]: unrecognized selector sent to instance 0x5dae960'

当我的其他代码工作正常

    NSMutableArray *streams = (NSMutableArray *)[feed valueForKey:@"from"];
    lueForKey:@"message"];
    // loop over all the stream objects and print their titles
    int index;
    NSMutableDictionary *stream;
for (index = 0; index < [feed count];index++) {
        stream = (NSMutableDictionary *)[streams objectAtIndex:index];

                NSLog(@"Name of sender is: %@", [stream valueForKey:@"message"]); 



    }

请帮助

这里是崩溃日志

2011-06-15 17:05:42.148 MultiSocial[8583:207] -[__NSArrayI isEqualToString:]: unrecognized selector sent to instance 0x5d05f50
2011-06-15 17:05:42.156 MultiSocial[8583:207] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayI isEqualToString:]: unrecognized selector sent to instance 0x5d05f50'
*** Call stack at first throw:
(
    0   CoreFoundation                      0x013cabe9 __exceptionPreprocess + 185
    1   libobjc.A.dylib                     0x0151f5c2 objc_exception_throw + 47
    2   CoreFoundation                      0x013cc6fb -[NSObject(NSObject) doesNotRecognizeSelector:] + 187
    3   CoreFoundation                      0x0133c366 ___forwarding___ + 966
    4   CoreFoundation                      0x0133bf22 _CF_forwarding_prep_0 + 50
    5   UIKit                               0x00649405 -[UITableViewLabel setText:] + 84
    6   MultiSocial                         0x00046147 -[FaceBookTable tableView:cellForRowAtIndexPath:] + 467
    7   UIKit                               0x0045f7fa -[UITableView(UITableViewInternal) _createPreparedCellForGlobalRow:withIndexPath:] + 634
    8   UIKit                               0x0045577f -[UITableView(UITableViewInternal) _createPreparedCellForGlobalRow:] + 75
    9   UIKit                               0x0046a450 -[UITableView(_UITableViewPrivate) _updateVisibleCellsNow:] + 1561
    10  UIKit                               0x00462538 -[UITableView layoutSubviews] + 242
    11  QuartzCore                          0x01e98451 -[CALayer layoutSublayers] + 181
    12  QuartzCore                          0x01e9817c CALayerLayoutIfNeeded + 220
    13  QuartzCore                          0x01e9137c _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 310
    14  QuartzCore                          0x01e910d0 _ZN2CA11Transaction6commitEv + 292
    15  QuartzCore                          0x01ec17d5 _ZN2CA11Transaction17observer_callbackEP19__CFRunLoopObservermPv + 99
    16  CoreFoundation                      0x013abfbb __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 27
    17  CoreFoundation                      0x013410e7 __CFRunLoopDoObservers + 295
    18  CoreFoundation                      0x01309bd7 __CFRunLoopRun + 1575
    19  CoreFoundation                      0x01309240 CFRunLoopRunSpecific + 208
    20  CoreFoundation                      0x01309161 CFRunLoopRunInMode + 97
    21  GraphicsServices                    0x0190f268 GSEventRunModal + 217
    22  GraphicsServices                    0x0190f32d GSEventRun + 115
    23  UIKit                               0x003fa42e UIApplicationMain + 1160
    24  MultiSocial                         0x00002740 main + 102
    25  MultiSocial                         0x000026d1 start + 53
)

Answer 1

根据崩溃日志 -[__NSArrayI isEqualToString:] 您的代码中有一些错误。在崩溃报告中可以清楚地看到 isEqualToString 方法适用于 NSString 对象，但在您的代码中它是在 NSArray 上调用的。

只需调试您的应用程序，您就会找到解决方案。

UPDATE

//Make sure that feed return an array for the key comments
 NSArray *streams = (NSArray *)[feed valueForKey:@"comments"];
 NSArray *streams1 = (NSArray *)[streams valueForKey:@"data"];

 NSLog(@"comments : %@",streams);

//When you are running loop only last index value will be copied into your dictionary named stream so remove the loop.

FaceBookTable *detailViewController = [[FaceBookTable alloc] initWithNibName:@"FaceBookTable" bundle:nil];
    // ...
    // Pass the selected object to the new view controller.
    detailViewController.fbGraph = fbGraph;
    detailViewController.dummyArray  = [ feed valueForKey:@"message"];
    detailViewController.dict = streams;

}

//你的tableView cellForRowAtIndexPath方法应该是这样的

//First get the dictionary

if(dict){
        NSDictionary *stream = (NSDictionary *)[dict objectAtIndex:indexPath.row];

       if(stream){
            NSDictionary * messages = (NSDictionary *[stream valueForKey:@"Message"];

            NSString *comment = [messages valueForKey:@"comment"];

           cell.textLabel.text = comment;
       }
}

Answer 2

你已经将 NSString 对象分配给 NSArray.so 使用断点进行调试

Answer 3

NSMutableArray *arr = [[[feed valueForKey:@"comments"]valueForKey:@"data" ]valueForKey:@"id"];
for (NSString* cid in [arr objectAtIndex:0]) {
    NSLog(@"cid is : %@ \n\n",cid);
}