How to check if a BOOL is null?

Posted by Sheehan Alam on Stack Overflow See other posts from Stack Overflow or by Sheehan Alam
Published on 2010-05-03T18:01:03Z Indexed on 2010/05/03 18:08 UTC
Read the original article Hit count: 195

Filed under:

objective-c

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cocoa-touch

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null

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iphone

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ipad

Is there a way I can check to see if a value is NULL/Nil before assigning it to a BOOL?

For example, I have a value in a NSDictionary that can be either TRUE/FALSE/NULL

mySTUser.current_user_following = [[results objectForKey:@"current_user_following"]boolValue];

When the value is NULL I get the following error

 *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[NSNull boolValue]: unrecognized selector sent to instance

I would like to be able to handle the NULL case.

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