Problem with json parsing in iphone application

My application is crashing whenever i click on submit button.

2011-08-09 19:41:29.590 ItcHotel[3888:207] reached here in didReceiveData 2011-08-09 19:41:29.593 ItcHotel[3888:207] * Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '* -[NSArray initWithObjects:count:]: a开发者_C百科ttempt to insert nil object at objects[0]' *** Call stack at first throw:

The error is self-explanatory. You are attempting to insert nil into the first position of the array (index 0). NSArray objects can not contain nil values. The C array passed as parameter to initWithObjects:count: must contain nil values.

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