ios - 如何删除具有用户定义 id 的 CoreData 对象？

Question

我有这样的对象

@interface Clubs : NSManagedObject

@property (nonatomic, retain) NSString * catname;
@property (nonatomic, retain) NSString * clubdescription;
@property (nonatomic, retain) NSString * clubid;
@property (nonatomic, retain) NSString * clubname;
@property (nonatomic, retain) NSString * distance;
@property (nonatomic, retain) NSString * logopath;
@property (nonatomic, retain) NSString * phone;
@property (nonatomic, retain) NSString * clubtype;

@end

我只想删除那些具有特定 clubid 的对象？

假设有20个俱乐部被添加到CoreData中，我只想删除这些clubid为120的对象。

谢谢

Answer 1

    -(void)deleteClubsEntity:(NSString*)clubId // pass the value 120
    {
        NSError *error = nil;
        NSManagedObjectContext *context = [self managedObjectContext];

        NSFetchRequest * fetch = [[NSFetchRequest alloc] init];

       [fetch setEntity:[NSEntityDescription entityForName:@"Clubs" inManagedObjectContext: context]];
       [fetch setPredicate:[NSPredicate predicateWithFormat:@"(clubid
 contains[cd] %@)",clubId]];

       NSArray * records = [context executeFetchRequest:fetch error:&error];
           for (NSManagedObject * record in records) {
                [context deleteObject:record];
            }
       [context save:&error];
    }