JSON錯誤的iOS：在JSON無效的頂級類型寫

Question

我無法搞清楚這個錯誤了：

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** +[NSJSONSerialization writeJSONObject:toStream:options:error:]: Invalid top-level type in JSON write' 

其中涉及到這個塊的代碼（基本上我創建一些JSON和發送它關閉到服務器）。我已經檢查過服務器，看看這個套接字是否被打開，它是哪個！

NSDictionary *blobData = [NSDictionary dictionaryWithObjectsAndKeys: 
          sendString,@"string", 
          nil]; 
NSString *blobString = [[NSString alloc] 
         initWithData:[NSJSONSerialization dataWithJSONObject:blobData options:kNilOptions error:&error] 
         encoding:NSUTF8StringEncoding]; 
NSLog(@"Blob Created: %@", blobString); 
NSDictionary *requestData = [NSDictionary dictionaryWithObjectsAndKeys: 
          @"send_string",@"request_type", 
          [NSNumber numberWithInt:0],@"security_level", 
          @"ios",@"device_type", 
          //No Email Provided, This is just for testing 
          blobData,@"blob", 
          nil]; 

NSData *JSONRequestData = NULL; 
if ([NSJSONSerialization isValidJSONObject:requestData]) { 
    NSLog(@"Proper JSON Object"); 
    JSONRequestData = [NSJSONSerialization dataWithJSONObject:requestData options:kNilOptions error:&error]; 
} 
else { 
    NSLog(@"requestData was not a proper JSON object"); 
    return FALSE; 
} 
NSLog(@"Error:%@",[[error userInfo] objectForKey:@"NSDebugDescription"]); 
NSLog(@"Contents of JSONRequestData: %@",[[NSString alloc] initWithData:JSONRequestData encoding:NSUTF8StringEncoding]); 
[NSJSONSerialization writeJSONObject:JSONRequestData toStream:outputStream options:0 error:&error]; 

我創建的JSON對象是否錯誤？也許有一個與我處理「斑點」

這裏的方式有問題就是我創建JSONRequestData

{"security_level":"0","request_type":"send_string","device_type":"ios","blob":{"string":"hello"}} 

Answer 1

writeJSONObject後NSLogs打印期待你想要的實際序列化對象發送，所以在這種情況下，你想通過它requestData對象，而不是JSONRequestData喜歡：

NSJSONSerialization writeJSONObject:requestData toStream:outputStream options:0 error:&error];