Question

我有一些核心数据条目，当应用程序启动时，这些条目都被提取并投入到数组中。当我使用deleteObject:从Core Data中删除对象时，我通过再次读取所有Core Data条目并将它们放入数组来刷新此数组。这里，Core Data对象被正确删除，并且未加载到新数组中。但是当我再次启动应用程序时，不会删除条目。他们又被装上了。

有没有人知道为什么我的Core Data对象没有被正确删除？

这是删除对象的地方：

// Define our table/entity to use  
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Notes" inManagedObjectContext:managedObjectContext];

// Setup the fetch request  
NSFetchRequest *request = [[NSFetchRequest alloc] init];
[request setEntity:entity];

// Fetch the records and handle an error  
NSError *error;  
NSMutableArray *allNotes = [[NSMutableArray alloc] initWithArray:[[managedObjectContext executeFetchRequest:request error:&error] mutableCopy]];

for(int i = 0; i < [allNotes count]; i++) {
    if([[allNotes objectAtIndex:i] identifier] == [[note objectAtIndex:0] identifier]) {
        [managedObjectContext deleteObject:[allNotes objectAtIndex:i]];
        NSLog(@"DELETING..");
        NSLog(@"%@", [allNotes objectAtIndex:i]);
    }
}

[request release];

这是我在启动时设置核心数据条目数组的方法

// Define our table/entity to use  
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Notes" inManagedObjectContext:managedObjectContext_];

    // Setup the fetch request  
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    [request setEntity:entity];

    // Fetch the records and handle an error  
    NSError *error;  
    globalNotes = [[NSMutableArray alloc] initWithArray:[[managedObjectContext_ executeFetchRequest:request error:&error] mutableCopy]];

    [request release];

    NSLog(@"NOTES ON STARTUP");
    NSLog(@"%@", globalNotes);

以下是我使用NSLog打印的一些数据。这可能有助于解决问题，并会显示这些注释已被删除，但会重新启用。

2011-04-25 20:11:40.877 Caltio[4039:707] NOTES ON STARTUP
2011-04-25 20:11:40.888 Caltio[4039:707] (
    "<Notes: 0x1855d0> (entity: Notes; id: 0x184cd0 <x-coredata://DC8B3294-6D87-4236-9E5C-29E11F7330FA/Notes/p2> ; data: <fault>)",
    "<Notes: 0x1858b0> (entity: Notes; id: 0x184ce0 <x-coredata://DC8B3294-6D87-4236-9E5C-29E11F7330FA/Notes/p3> ; data: <fault>)"
)
2011-04-25 20:16:41.561 Caltio[4039:707] DELETING..
2011-04-25 20:16:41.569 Caltio[4039:707] <Notes: 0x1855d0> (entity: Notes; id: 0x184cd0 <x-coredata://DC8B3294-6D87-4236-9E5C-29E11F7330FA/Notes/p2> ; data: {
    added = "2011-04-25 17:56:15 +0000";
    identifier = 2567446185;
    note = Test;
    updated = 0;
})
2011-04-25 20:16:41.589 Caltio[4039:707] NOTES AFTER REFRESH:
2011-04-25 20:16:41.595 Caltio[4039:707] (
    "<Notes: 0x1858b0> (entity: Notes; id: 0x184ce0 <x-coredata://DC8B3294-6D87-4236-9E5C-29E11F7330FA/Notes/p3> ; data: {\n    added = \"2011-04-25 17:57:26 +0000\";\n    identifier = 2567446127;\n    note = Test;\n    updated = 0;\n})"
)

2011-04-25 20:17:05.103 Caltio[4052:707] NOTES ON STARTUP
2011-04-25 20:17:05.115 Caltio[4052:707] (
    "<Notes: 0x1bee60> (entity: Notes; id: 0x1be570 <x-coredata://DC8B3294-6D87-4236-9E5C-29E11F7330FA/Notes/p2> ; data: <fault>)",
    "<Notes: 0x1bf150> (entity: Notes; id: 0x1bdcd0 <x-coredata://DC8B3294-6D87-4236-9E5C-29E11F7330FA/Notes/p3> ; data: <fault>)"
)

Answer 1

你保存了managedObjectContext吗？据我了解，添加，修改和删除对象只会影响其内存中的表示。您还需要保存上下文以保持它。

Core Data删除了在启动时重新出现的对象

1 个答案: