核心数据不保存 NSString

Question

目前在我的核心数据保存中发现了一个问题。由于某种原因，一个 NSString 没有被正确保存，无论如何总是返回 0 。以下是我当前的代码。

appDelegate =(NotaciousAppDelegate *) [[UIApplication sharedApplication] delegate];

        NSEntityDescription *entity = [NSEntityDescription entityForName:@"Note" inManagedObjectContext:appDelegate.managedObjectContext];
        NSArray *fetchedNotes;

        NSArray *notes = [object valueForKey:@"result"];
        for (NSDictionary *singleNote in notes){

            noteFetch=[[NSFetchRequest alloc] init];
            [noteFetch setEntity:entity];
            NSPredicate *pred=[NSPredicate predicateWithFormat:@"ID==%@",[singleNote objectForKey:@"note id"]];
            [noteFetch setPredicate:pred];

            NSError *fetchError=nil;
            fetchedNotes=[appDelegate.managedObjectContext executeFetchRequest:noteFetch error:&fetchError];

            if (fetchError!=nil) {
                NSLog(@"syncNotes fetchError=%@,details=%@",fetchError,fetchError.userInfo);
            }
            if ([fetchedNotes count]==0) {


                NSString *notelocked = [singleNote objectForKey:@"note locked"];

                NSString *notecreated = [singleNote objectForKey:@"note created"];
                NSString *noteupdated = [singleNote valueForKey:@"note updated"];
                NSString *notetitle = [singleNote objectForKey:@"note title"];
                NSString *notesummary = [singleNote objectForKey:@"note summary"];
                NSString *noteid = [singleNote objectForKey:@"note id"];
                NSString *notecontent = [singleNote objectForKey:@"note content"];

                NSString *formattedTitle = [NSString decodeShit:notetitle];
                NSString *formattedSummary = [NSString decodeShit:notesummary];
                NSString *formattedContent = [NSString decodeShit:notecontent];


                NSLog(@"Note Title: %@",formattedTitle);
                NSLog(@"Note Summary: %@",formattedSummary);
                NSLog(@"Note ID: %@",noteid);
                NSLog(@"Note Content: %@",formattedContent);
                NSLog(@"Note Created: %@",notecreated);
                NSLog(@"Note Updated: %@",noteupdated);
                NSLog(@"Note Locked: %@",notelocked);

                newNote = [NSEntityDescription insertNewObjectForEntityForName:@"Note" inManagedObjectContext:appDelegate.managedObjectContext];
                [newNote autorelease];

                [newNote setValue:formattedContent forKey:@"content"];
                [newNote setValue:formattedSummary forKey:@"summary"];
                [newNote setValue:formattedTitle forKey:@"title"];
                [newNote setValue:noteid forKey:@"ID"];
                [newNote setValue:notecreated forKey:@"created"];
                [newNote setValue:noteupdated forKey:@"updated"];
                [newNote setValue:notelocked forKey:@"locked"];

                NSLog(@"Note Updated in MOC:%@",[newNote valueForKey:@"updated"]);

                NSError *error = nil;
                if (![appDelegate.managedObjectContext save:&error]) {
                    NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
                    abort();
                }


            }

            [noteFetch release];

        }

尝试保存 updated 字符串时会出现问题。出于某种原因，无论那里有什么字符串，它都不会保存到 Core Data 属性中。

我正在努力寻找任何连贯的理由让它不保存，但我认为这是可能的。这是此应用程序上架之前需要排序的最后一个问题。任何帮助都会很棒！

编辑

没有错误，调试控制台中只有以下输出。

 2011-04-24 10:53:22.815 Notacious[5660:707] Note Title: Hello there!
 2011-04-24 10:53:22.816 Notacious[5660:707] Note Summary: 
 2011-04-24 10:53:22.817 Notacious[5660:707] Note ID: 1240
 2011-04-24 10:53:22.817 Notacious[5660:707] Note Content: Hello there!

 This is a new note made from the iPhone client. Woot?
 2011-04-24 10:53:22.818 Notacious[5660:707] Note Created: Thu Apr 21 19:19:39 -0700 2011
 2011-04-24 10:53:22.819 Notacious[5660:707] Note Updated: Thu Apr 21 19:19:39 -0700 2011
 2011-04-24 10:53:22.820 Notacious[5660:707] Note Locked: 0
 2011-04-24 10:53:22.823 Notacious[5660:707] Note Updated in MOC:0

Answer 1

你确定字典中的“note updated”不是 NSDate 而不是 NSString？日志输出让它看起来很糟糕，就像你在那里有一个 NSDate。

如果是这样，您将需要使用 NSDateFormatter 将其保存到 NSString 对象属性中。

Answer 2

以下代码有效。

appDelegate =(NotaciousAppDelegate *) [[UIApplication sharedApplication] delegate];

        NSEntityDescription *entity = [NSEntityDescription entityForName:@"Note" inManagedObjectContext:appDelegate.managedObjectContext];
        NSArray *fetchedNotes;

        NSArray *notes = [object valueForKey:@"result"];
        for (NSDictionary *singleNote in notes){

            noteFetch=[[NSFetchRequest alloc] init];
            [noteFetch setEntity:entity];
            NSPredicate *pred=[NSPredicate predicateWithFormat:@"ID==%@",[singleNote objectForKey:@"note id"]];
            [noteFetch setPredicate:pred];

            NSError *fetchError=nil;
            fetchedNotes=[appDelegate.managedObjectContext executeFetchRequest:noteFetch error:&fetchError];

            if (fetchError!=nil) {
                NSLog(@"syncNotes fetchError=%@,details=%@",fetchError,fetchError.userInfo);
            }
            if ([fetchedNotes count]==0) {

                NSString *notelocked = [singleNote objectForKey:@"note locked"];

                NSString *noteupdated = [singleNote valueForKey:@"note updated"];
                NSString *notecreated = [singleNote objectForKey:@"note created"];
                NSString *notetitle = [singleNote objectForKey:@"note title"];
                NSString *notesummary = [singleNote objectForKey:@"note summary"];
                NSString *noteid = [singleNote objectForKey:@"note id"];
                NSString *notecontent = [singleNote objectForKey:@"note content"];

                NSString *formattedTitle = [NSString decodeShit:notetitle];
                NSString *formattedSummary = [NSString decodeShit:notesummary];
                NSString *formattedContent = [NSString decodeShit:notecontent];

                newNote = [NSEntityDescription insertNewObjectForEntityForName:@"Note" inManagedObjectContext:appDelegate.managedObjectContext];

                [newNote setValue:formattedContent forKey:@"content"];
                [newNote setValue:formattedSummary forKey:@"summary"];
                [newNote setValue:formattedTitle forKey:@"title"];
                [newNote setValue:noteid forKey:@"ID"];
                [newNote setValue:notecreated forKey:@"created"];
                [newNote setValue:noteupdated forKey:@"noteupdated"];
                [newNote setValue:notelocked forKey:@"locked"];

                NSError *error = nil;
                if (![appDelegate.managedObjectContext save:&error]) {
                    NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
                    abort();
                }


            }

            [noteFetch release];

        }

CoreData 似乎不喜欢我访问名称为 updated 的属性。