Ios 读取时出现MagicalRecord问题？

因此，我希望根据用户选择显示一些信息，并且我希望将此选择保存在coreData中，以便将来表视图仅显示用户想要的信息

我正在使用MagicalRecord：

+(void)insertNewSeccion:(NSString *)seccion{

[Seccion MR_truncateAll];

[MagicalRecord saveUsingCurrentThreadContextWithBlock:^(NSManagedObjectContext *localContext) {

    Seccion *myseccion = [Seccion MR_createEntity];

    myseccion.seccion = seccion;

    //[[NSManagedObjectContext MR_defaultContext] MR_saveNestedContexts];

} completion:^(BOOL success, NSError *error) {

}];

}

我这样称呼它写：

     - (IBAction)PrepaAction:(id)sender {

    [CoreDataBase insertNewSeccion:@"prep"];

    [self reloadSeccion];
}

以及阅读：

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{

   if ([[CoreDataBase oneSeccion]isEqualToString:@"prep"]) {
        return _TitlePrep.count;
    }
    return 0;

}

我得到了这个日志：

[NSManagedObjectContext(MagicalRecord) MR_contextWithStoreCoordinator:](0x4ac0ac) -> Created Context UNNAMED
2014-02-09 16:07:15.206 CMT[54120:70b] +[NSManagedObjectContext(MagicalRecord) MR_setRootSavingContext:](0x4ac0ac) Set Root Saving Context: <NSManagedObjectContext: 0xc871050>
2014-02-09 16:07:15.207 CMT[54120:70b] +[NSManagedObjectContext(MagicalRecord) MR_newMainQueueContext](0x4ac0ac) Created Main Queue Context: <NSManagedObjectContext: 0xc870f00>
2014-02-09 16:07:15.208 CMT[54120:70b] +[NSManagedObjectContext(MagicalRecord) MR_setDefaultContext:](0x4ac0ac) Set Default Context: <NSManagedObjectContext: 0xc870f00>
2014-02-09 16:07:19.722 CMT[54120:70b] -[NSManagedObjectContext(MagicalSaves) MR_saveWithOptions:completion:](0xc870f00) → Saving <NSManagedObjectContext (0xc870f00): *** DEFAULT ***> on *** MAIN THREAD ***
2014-02-09 16:07:19.723 CMT[54120:70b] -[NSManagedObjectContext(MagicalSaves) MR_saveWithOptions:completion:](0xc870f00) → Save Parents? 1
2014-02-09 16:07:19.723 CMT[54120:70b] -[NSManagedObjectContext(MagicalSaves) MR_saveWithOptions:completion:](0xc870f00) → Save Synchronously? 0
2014-02-09 16:07:19.768 CMT[54120:70b] -[Seccion isEqualToString:]: unrecognized selector sent to instance 0xb43e580
2014-02-09 16:07:19.782 CMT[54120:70b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Seccion isEqualToString:]: unrecognized selector sent to instance 0xb43e580'

那怎么了？问题是在阅读时，因为如果我对tableview进行注释，它会写入，但不会读取。谢谢你的帮助

-[Seccion isEqualToString:]：发送到实例0xb43e580的选择器无法识别

实例0xb43e580不是字符串，但它是一个类为Seccion的对象。您应该查找名为seccion的属性

更改您的行数部分：

您可能想考虑为属性使用不同的名称。具有与类相同的属性可能会令人困惑

[NSManagedObjectContext(MagicalRecord) MR_contextWithStoreCoordinator:](0x4ac0ac) -> Created Context UNNAMED
2014-02-09 16:07:15.206 CMT[54120:70b] +[NSManagedObjectContext(MagicalRecord) MR_setRootSavingContext:](0x4ac0ac) Set Root Saving Context: <NSManagedObjectContext: 0xc871050>
2014-02-09 16:07:15.207 CMT[54120:70b] +[NSManagedObjectContext(MagicalRecord) MR_newMainQueueContext](0x4ac0ac) Created Main Queue Context: <NSManagedObjectContext: 0xc870f00>
2014-02-09 16:07:15.208 CMT[54120:70b] +[NSManagedObjectContext(MagicalRecord) MR_setDefaultContext:](0x4ac0ac) Set Default Context: <NSManagedObjectContext: 0xc870f00>
2014-02-09 16:07:19.722 CMT[54120:70b] -[NSManagedObjectContext(MagicalSaves) MR_saveWithOptions:completion:](0xc870f00) → Saving <NSManagedObjectContext (0xc870f00): *** DEFAULT ***> on *** MAIN THREAD ***
2014-02-09 16:07:19.723 CMT[54120:70b] -[NSManagedObjectContext(MagicalSaves) MR_saveWithOptions:completion:](0xc870f00) → Save Parents? 1
2014-02-09 16:07:19.723 CMT[54120:70b] -[NSManagedObjectContext(MagicalSaves) MR_saveWithOptions:completion:](0xc870f00) → Save Synchronously? 0
2014-02-09 16:07:19.768 CMT[54120:70b] -[Seccion isEqualToString:]: unrecognized selector sent to instance 0xb43e580
2014-02-09 16:07:19.782 CMT[54120:70b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Seccion isEqualToString:]: unrecognized selector sent to instance 0xb43e580'

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
   if ([[[CoreDataBase oneSeccion] seccion] isEqualToString:@"prep"]) {
   //  ^^                          ^^^^^^^^          
   return _TitlePrep.count;
   }
   return 0;
}