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Ios 检查核心数据的结果并删除_Ios_Objective C_Core Data - Fatal编程技术网

Ios 检查核心数据的结果并删除

Ios 检查核心数据的结果并删除,ios,objective-c,core-data,Ios,Objective C,Core Data,我需要为我的核心数据创建一个方法。此方法应检查实体部分和夹具中是否有任何结果。如果存在,则删除其中的所有对象 我该怎么做?我试过了,但什么也没做 NSManagedObjectContext *context = [self managedObjectContext]; NSManagedObject *numberOfFixtures = [NSEntityDescription insertNewObjectForEntityForName:@"Fixture

我需要为我的核心数据创建一个方法。此方法应检查实体
部分
夹具
中是否有任何结果。如果存在,则删除其中的所有对象

我该怎么做?我试过了,但什么也没做

NSManagedObjectContext *context = [self managedObjectContext];
NSManagedObject *numberOfFixtures = [NSEntityDescription
                insertNewObjectForEntityForName:@"Fixture"
                inManagedObjectContext:context];

NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Fixture" inManagedObjectContext:context];
[fetchRequest setEntity:entity];
self.theFixtures = [[context executeFetchRequest:fetchRequest error:nil] mutableCopy];

for (numberOfFixtures *fixture in self.theFixtures) {
    [context deleteObject:fixture];
}

NSError *error;
[context save:&error];
试试这个

 NSManagedObjectContext *context = [self managedObjectContext];
 NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
NSEntityDescription *entity = [NSEntityDescription entityForName:@"Fixture" inManagedObjectContext:context];
[fetchRequest setEntity:entity];
 self.theFixtures = [[context executeFetchRequest:fetchRequest error:nil] mutableCopy];

 for (NSManagedObject *fixture in self.theFixtures) {
     [context deleteObject:fixture];
 }
 NSError *error;
 [context save:&error];

[上下文保存:&错误]在循环内是个坏主意。fixture*fixture。Fixtures什么应该是fetchRequest?@user3423384假定
Fixture
NSManagedObject
子类和
self。Fixtures
是执行fetchRequest时
上下文
返回的数组。二进制表达式('NSManagedObject*'和'NSManagedObject*'的操作数无效)@user3423384您是否使用了更新的代码?如果没有,请查看编辑。您已经在此处添加了一个问题。是一样的!!