迅速:

let fetchRequest = NSFetchRequest()
fetchRequest.entity = NSEntityDescription.entityForName(entityName, inManagedObjectContext: context)
fetchRequest.includesPropertyValues = false

var error:NSError?
if let results = context.executeFetchRequest(fetchRequest, error: &error) as? [NSManagedObject] {
    for result in results {
        context.deleteObject(result)
    }

    var error:NSError?
    if context.save(&error) {
        // do something after save

    } else if let error = error {
        println(error.userInfo)
    }

} else if let error = error {
    println("error: \(error)")
}

NSBatchDeleteRequest Swift 5.5和Xcode 13.2

删除SQLite持久存储中的对象，而不加载到内存中。在持久存储上执行的更改不会反映在当前内存中的对象中。

执行批量删除之后，从持久存储中删除内存中的所有对象。

下面是执行batchDeleteRequest的一些方便的扩展方法

extension NSManagedObject {
    
    private static var entityName: String {
        return String(describing: self)
    }
    
    static func fetchRequest<Self>(
        with predicate: NSPredicate? = nil,
        configureBlock: ((NSFetchRequest<Self>) -> Void)? = nil
    ) -> NSFetchRequest<Self> where Self: NSFetchRequestResult {
        let request = NSFetchRequest<Self>(entityName: entityName)
        request.predicate = predicate
        configureBlock?(request)
        return request
    }
    
    static func batchDelete(with fetchRequest: NSFetchRequest<NSFetchRequestResult>,
                            in context: NSManagedObjectContext) {
        let batchDeteleRequest = NSBatchDeleteRequest(fetchRequest: fetchRequest)
        batchDeteleRequest.resultType = .resultTypeObjectIDs
        do {
            if let fetchResult = try context.execute(batchDeteleRequest) as? NSBatchDeleteResult,
               let deletedManagedObjectIds = fetchResult.result as? [NSManagedObjectID], !deletedManagedObjectIds.isEmpty {
                let changes = [NSDeletedObjectsKey: deletedManagedObjectIds]
                NSManagedObjectContext.mergeChanges(fromRemoteContextSave: changes, into: [context])
            }
        } catch {
            print("Error while executing batchDeleteRequest: \(error.localizedDescription)")
        }
    }
}

示例:我们可以通过传递fetchRequest调用batchDelete静态方法批量删除实体

class Entity: NSManagedObject {
    @NSManaged var name: String?
    @NSManaged var value: String?
}

extension Entity {
    
    static func executeBatchDelete(in context: NSManagedObjectContext) {
        let predicate = NSPredicate(format: "\(#keyPath(Entity.value)) == %@)", "abc")
        let deleteRequest: NSFetchRequest<NSFetchRequestResult> = Entity.fetchRequest(with: predicate)
        Entity.batchDelete(with: deleteRequest, in: context)
    }
}

一个很好的答案已经贴出来了，这只是一个推荐!

一个好方法是添加一个类别到NSManagedObject和实现一个方法，就像我做的:

头文件(例如NSManagedObject+Ext.h)

@interface NSManagedObject (Logic)

+ (void) deleteAllFromEntity:(NSString*) entityName;

@end

代码文件:(例如NSManagedObject+Ext.m)

@implementation NSManagedObject (Logic)

+ (void) deleteAllFromEntity:(NSString *)entityName {
    NSManagedObjectContext *managedObjectContext = [AppDelegate managedObjectContext];
    NSFetchRequest * allRecords = [[NSFetchRequest alloc] init];
    [allRecords setEntity:[NSEntityDescription entityForName:entityName inManagedObjectContext:managedObjectContext]];
    [allRecords setIncludesPropertyValues:NO];
    NSError * error = nil;
    NSArray * result = [managedObjectContext executeFetchRequest:allRecords error:&error];
    for (NSManagedObject * profile in result) {
        [managedObjectContext deleteObject:profile];
    }
    NSError *saveError = nil;
    [managedObjectContext save:&saveError];
}

@end

．.． 你唯一要做的就是从应用程序委托获取managedObjectContext，或者你在哪里都有它;)

之后你可以这样使用它:

[NSManagedObject deleteAllFromEntity:@"EntityName"];

进一步的优化可以是删除entityname的参数，而从clazzname获取名称。这将导致使用:

[ClazzName deleteAllFromEntity];

一个更干净的impl(作为NSManagedObjectContext的类别):

@implementation NSManagedObjectContext (Logic)

- (void) deleteAllFromEntity:(NSString *)entityName {
    NSFetchRequest * allRecords = [[NSFetchRequest alloc] init];
    [allRecords setEntity:[NSEntityDescription entityForName:entityName inManagedObjectContext:self]];
    [allRecords setIncludesPropertyValues:NO];
    NSError * error = nil;
    NSArray * result = [self executeFetchRequest:allRecords error:&error];
    for (NSManagedObject * profile in result) {
        [self deleteObject:profile];
    }
    NSError *saveError = nil;
    [self save:&saveError];
}

@end

那时的用法:

[managedObjectContext deleteAllFromEntity:@"EntityName"];

Swift4+和Xcode 10+ 使用下面的代码删除实体中的所有记录。

func deleteAllRecords(entity : String) {

        let managedContext = CoreDataManager.sharedManager.persistentContainer.viewContext //your context
        let deleteFetch = NSFetchRequest<NSFetchRequestResult>(entityName: entity)
        let deleteRequest = NSBatchDeleteRequest(fetchRequest: deleteFetch)
        
        do {
            try managedContext.execute(deleteRequest)
            try managedContext.save()
        } catch {
            print ("There was an error")
        }
    }

如何使用

self.deleteEntityData(entity: "YOUR_ENTITY_NAME")

Swift 4, iOS 12和Xcode 10更新

100%工作，只是剪切和粘贴

只要把这个函数放在相关的类中，并在viewDidLoad()或任何地方或在一个函数或按钮下调用这个函数self.deleteData()，这样通过单击一个按钮，所有来自实体的数据都应该被删除，并替换“myEntity”作为你在核心数据中定义的实体

func deleteData() {
    let appDel:AppDelegate = (UIApplication.shared.delegate as! AppDelegate)
    let context:NSManagedObjectContext = appDel.persistentContainer.viewContext
    let fetchRequest = NSFetchRequest<NSFetchRequestResult>(entityName: "myEntity")
    fetchRequest.returnsObjectsAsFaults = false         
    do {
        let results = try context.fetch(fetchRequest)
        for managedObject in results {
            if let managedObjectData: NSManagedObject = managedObject as? NSManagedObject {
                context.delete(managedObjectData)
            }
        }
    } catch let error as NSError {
        print("Deleted all my data in myEntity error : \(error) \(error.userInfo)")
    }
}

如果实体包含很多条目，最好的方法是这样，因为它节省内存

 - (void)deleteAll:(NSManagedObjectContext *)managedObjectContext entityName:(NSString *)entityName
{
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    [managedObjectContext setUndoManager:nil];
    NSEntityDescription *entity = [NSEntityDescription entityForName:entityName inManagedObjectContext:managedObjectContext];
    [fetchRequest setEntity:entity];
    [fetchRequest setIncludesPropertyValues:NO];
    [fetchRequest setFetchLimit:100]; // you can change this number if you want
    NSError *error;
    NSArray *items = [managedObjectContext executeFetchRequest:fetchRequest error:&error];
    while ([items count] > 0) {
        @autoreleasepool {
            for (NSManagedObject *item in items) {
                [managedObjectContext deleteObject:item];
            }
            if (![managedObjectContext save:&error]) {
                NSLog(@"Error deleting %@ - error:%@",self.entityName, error);
            }
        }
        items = [managedObjectContext executeFetchRequest:fetchRequest error:&error];
    }
}