作为一个快速参考，以节省在其他地方搜索-删除后重新创建持久存储可以用:

if (![persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:nil error:&error]) {
// do something with the error
}

你可以删除SQLite文件-但我选择通过一个函数单独清除表来做到这一点:

- (void) deleteAllObjects: (NSString *) entityDescription  {
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:entityDescription inManagedObjectContext:_managedObjectContext];
    [fetchRequest setEntity:entity];

    NSError *error;
    NSArray *items = [_managedObjectContext executeFetchRequest:fetchRequest error:&error];
    [fetchRequest release];


    for (NSManagedObject *managedObject in items) {
        [_managedObjectContext deleteObject:managedObject];
        DLog(@"%@ object deleted",entityDescription);
    }
    if (![_managedObjectContext save:&error]) {
        DLog(@"Error deleting %@ - error:%@",entityDescription,error);
    }

}

我选择逐表执行的原因是，它使我在编程时确认删除表的内容是合理的，并且没有我宁愿保留的数据。

这样做会比仅仅删除文件慢得多，如果我这个方法花费太长时间，我将更改为文件删除。

下面这个版本可以删除每个表中的每条记录。

斯威夫特4

static func resetDatabase() {
    do {
        try dataStore.persistentStoreCoordinator.managedObjectModel.entities.forEach { (entity) in
            if let name = entity.name {
                let fetch = NSFetchRequest<NSFetchRequestResult>(entityName: name)
                let request = NSBatchDeleteRequest(fetchRequest: fetch)
                try mainContext.execute(request)
            }
        }

        try mainContext.save()
    } catch {
        print("error resenting the database: \(error.localizedDescription)")
    }
}

接受的答案是正确的，通过NSFileManager删除URL是正确的，但正如在iOS 5+编辑中所述，持久存储不仅仅由一个文件表示。对于SQLite存储，它是*。sqlite, *。Sqlite-shm和*。sqlite-wal……幸运的是，自从iOS 7+我们可以使用方法

[NSPersistentStoreCoordinator + removeUbiquitousContentAndPersistentStoreAtURL选项:错误:):

为了处理删除，代码应该是这样的:

NSPersistentStore *store = ...;
NSError *error;
NSURL *storeURL = store.URL;
NSString *storeName = ...;
NSPersistentStoreCoordinator *storeCoordinator = ...;
[storeCoordinator removePersistentStore:store error:&error];
[NSPersistentStoreCoordinator removeUbiquitousContentAndPersistentStoreAtURL:storeURL.path options:@{NSPersistentStoreUbiquitousContentNameKey: storeName} error:&error];

龙道9+ Swift 2

删除所有实体中的所有对象

func clearCoreDataStore() {
    let entities = managedObjectModel.entities
    for entity in entities {
        let fetchRequest = NSFetchRequest(entityName: entity.name!)
        let deleteReqest = NSBatchDeleteRequest(fetchRequest: fetchRequest)
        do {
            try context.executeRequest(deleteReqest)
        } catch {
            print(error)
        }
    }
}

我采取了Grouchal的代码，为了加快速度，我使用了并发模式的枚举(NSEnumerationConcurrent)，它比for循环快了一点(在我的应用程序中，我为测试人员添加了这个功能，以便他们可以清除数据和做测试用例，而不是删除和安装应用程序)

- (void)resetObjects
{
    [self deleteAllObjectsInEntity:@"Entity1"];
    [self deleteAllObjectsInEntity:@"Entity2"];
    [self deleteAllObjectsInEntity:@"Entity3"];
    [self deleteAllObjectsInEntity:@"Entity4"];
}

-(void) deleteAllObjectsInEntity:(NSString*) entityName
{
    MainDataContext *coreDataContext = [MainDataContext sharedInstance];
    NSManagedObjectContext *currentContext = coreDataContext.managedObjectContext;
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:entityName inManagedObjectContext:currentContext];
    [fetchRequest setEntity:entity];

    NSError *error;
    NSArray *items = [currentContext executeFetchRequest:fetchRequest error:&error];

    [items enumerateObjectsWithOptions:NSEnumerationConcurrent usingBlock:^(NSManagedObject * obj, NSUInteger idx, BOOL *stop) {
        [currentContext deleteObject:obj];
    }];


    if (![currentContext save:&error]) {
        NSLog(@"Error deleting %@ - error:%@",entityName,error);
    }
}