这段代码适用于iOS 9及以下版本

class func deleteAllRecords(in entity : String) // entity = Your_Entity_Name
    {

        let context = CoreDataStack.getContext() // Note:- Replace your context here with CoreDataStack.getContext()
        let deleteFetch = NSFetchRequest<NSFetchRequestResult>(entityName: entity)
        if #available(iOS 9, *)
        {
            let deleteRequest = NSBatchDeleteRequest(fetchRequest: deleteFetch)
            do
            {
                try context.execute(deleteRequest)
                try context.save()
            }
            catch
            {
                print("There was an error:\(error)")
            }
        }
        else
        {
            do{
                let deleteRequest = try context.fetch(deleteFetch)
                for anItem in deleteRequest {
                    context.delete(anItem as! NSManagedObject)
                }
            }
            catch
            {
                print("There was an error:\(error)")
            }
        }
        CoreDataStack.saveContext() // Note:- Replace your savecontext here with CoreDataStack.saveContext()
    }

Dave Delongs的Swift 2.0回答让我崩溃了(在iOS 9中)

但这个方法奏效了:

let fetchRequest = NSFetchRequest(entityName: "Car")
let deleteRequest = NSBatchDeleteRequest(fetchRequest: fetchRequest)

    do {
        try managedObjectContext.executeRequest(deleteRequest)
        try managedObjectContext.save()
    }
    catch let error as NSError {
       // Handle error
    }

这段代码适用于iOS 9及以下版本

class func deleteAllRecords(in entity : String) // entity = Your_Entity_Name
    {

        let context = CoreDataStack.getContext() // Note:- Replace your context here with CoreDataStack.getContext()
        let deleteFetch = NSFetchRequest<NSFetchRequestResult>(entityName: entity)
        if #available(iOS 9, *)
        {
            let deleteRequest = NSBatchDeleteRequest(fetchRequest: deleteFetch)
            do
            {
                try context.execute(deleteRequest)
                try context.save()
            }
            catch
            {
                print("There was an error:\(error)")
            }
        }
        else
        {
            do{
                let deleteRequest = try context.fetch(deleteFetch)
                for anItem in deleteRequest {
                    context.delete(anItem as! NSManagedObject)
                }
            }
            catch
            {
                print("There was an error:\(error)")
            }
        }
        CoreDataStack.saveContext() // Note:- Replace your savecontext here with CoreDataStack.saveContext()
    }

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)
    }
}

对于Swift 2.0:

class func clearCoreData(entity:String) {
  let fetchRequest = NSFetchRequest()
  fetchRequest.entity = NSEntityDescription.entityForName(entity, inManagedObjectContext: moc!)
  fetchRequest.includesPropertyValues = false
  do {
    if let results = try moc!.executeFetchRequest(fetchRequest) as? [NSManagedObject] {
      for result in results {
        moc!.deleteObject(result)
      }

      try moc!.save()
    }
  } catch {
    LOG.debug("failed to clear core data")
  }
}

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)")
    }
}