目前我正在编写一个应用程序(目标iOS 6,启用了ARC),它使用JSON进行数据传输,使用Core Data进行持久存储.JSON数据由PHP脚本通过json_encode从MySQL数据库生成.
我的问题是,对于某些表中的数据,以下代码失败:
- (NSDictionary *)executeFetch:(NSString *)query
{
NSURL *requesturl = [NSURL URLWithString:[query stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
NSError *dataError = nil;
self.jsonData = [NSData dataWithContentsOfURL:requesturl options:kNilOptions error:&dataError];
NSError *error = nil;
self.jsonSerializationResult = [NSJSONSerialization JSONObjectWithData:self.jsonData options:NSJSONReadingMutableContainers|NSJSONReadingMutableLeaves error:&error];
return self.jsonSerializationResult;
}
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该程序总是在EXC_BAD_ACCESS错误的位置崩溃,它表示self.jsonSerializationResult和Instruments说有一个Zombie被检测到.我知道这意味着我发送消息的一些对象是零,但我无法找到如何解决它...这就是乐器所说的:
# Address Category Event Type RefCt Timestamp Size Responsible Library Responsible Caller
0 0xa1b8a70 CFString (mutable) Malloc 1 00:01.603.081 32 Foundation -[NSPlaceholderMutableString initWithBytesNoCopy:length:encoding:freeWhenDone:]
1 0xa1b8a70 CFString (mutable) Release 0 00:01.603.137 0 Foundation newJSONValue
2 0xa1b8a70 CFString (mutable) Zombie -1 00:01.603.259 0 …Run Code Online (Sandbox Code Playgroud)