iOS : -[__NSCFDictionary _expandedCFCharacterSet]: error

Question

I am working on iOS application.In one scenario I am sending phone number and some text message to server like this

- (void)postData:(NSString *)message :(NSString *)mobileno
{

NSLog(@"postData is called");
@try
{
    NSString *urlString = [NSString stringWithFormat:@"http://anlgelist.commonshell.net/api/account"];
    NSURL *url = [[NSURL alloc] initWithString:urlString];
    NSMutableURLRequest *urlRequest1=[NSMutableURLRequest requestWithURL:url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0];
    NSMutableDictionary *postDictionary=[[NSMutableDictionary alloc]init];
  [postDictionary setValue:message forKey:@"Message"];
  [postDictionary setValue:mobileno forKey:@"MobileNumber"];
      SBJsonWriter *jsonWriter = [SBJsonWriter new];
   NSError *error = nil;
    NSLog(@"~~~~~~~~ postDictionary is %@",postDictionary);

    NSString * jsonDataString =[jsonWriter stringWithObject:postDictionary];

    if ( ! jsonDataString )
    {
        NSLog(@"Error: %@", error);
    }

    NSData *requestData = [NSData dataWithBytes:[jsonDataString UTF8String] length:[jsonDataString length]];
    [urlRequest1 setHTTPMethod:@"PUT"];
    [urlRequest1 setValue:@"application/json" forHTTPHeaderField:@"content-type"];
    [urlRequest1 setHTTPBody: requestData];
    connection1 = [NSURLConnection connectionWithRequest:urlRequest1 delegate:self];

}
@catch (NSException *exception)
{
    ////NSLog(@"exception is %@",exception);

    @throw exception;
}

}

I am continuously calling this web service to send the details.But sometimes I am getting the following error and app getting crashed.

<Error>: -[__NSCFDictionary _expandedCFCharacterSet]: unrecognized selector sent to instance 0x14fdf350

I had not faced this kind of error previously.I googled but not found the solution.

Crash Report is

Answer 1

I am not sure it will work fine, but in your case the object has released and you try to access that, So i have prefered this solution,please try this.

SBJsonWriter *jsonWriter = [[SBJsonWriter new]retain];