iOS開發筆記 － MutableCopy

今天一直發生底下的exception：

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[__NSCFDictionary setObject:forKey:]: mutating method sent to immutable object'

仔細查了之後才知道，是在讀取file時，用了以下這樣的code

NSMutableDictionary *fileContent = [[[NSMutableDictionary alloc] initWithContentsOfFile:_filePath] autorelease];

_list       = @"list";

_content    = @"content";

_objects        = [[fileContent objectForKey:_list] copy];

_qaDescriptions = [[fileContent objectForKey:_content] copy];

copy改成mutableCopy即可