Ios Swift:executeFetchRequest:无法转换类型为';任何对象';
我对executeFetchRequest有一些问题Ios Swift:executeFetchRequest:无法转换类型为';任何对象';,ios,iphone,swift,Ios,Iphone,Swift,我对executeFetchRequest有一些问题 import UIKit import CoreData class BeaconDB: NSObject { var addStatus: BeaconAddStatus! enum BeaconAddStatus{ case DUPLICATE_IN_AD case ADDED_SUCCESSFULL case ERROR_IN_ADD }
import UIKit
import CoreData
class BeaconDB: NSObject {
var addStatus: BeaconAddStatus!
enum BeaconAddStatus{
case DUPLICATE_IN_AD
case ADDED_SUCCESSFULL
case ERROR_IN_ADD
}
func addNewBeacon(beacon: BeaconData) -> BeaconAddStatus{
print("ADDNewBeacon")
print("uuid: %@ \(beacon.uuid)")
let appDelegate: AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let context: NSManagedObjectContext = appDelegate.managedObjectContext
let entityDesc: NSEntityDescription = NSEntityDescription.entityForName("Beacon", inManagedObjectContext: context)!
let request: NSFetchRequest = NSFetchRequest()
let predSearch: NSPredicate = NSPredicate(format: "(uuid = %@) AND (major = %@) AND (minor = %@) \(beacon.uuid), \(beacon.major), \(beacon.minor)")
request.entity = entityDesc
request.predicate = predSearch
do {
let existingBeacon: Beacons = try context.executeFetchRequest(request)
// success ...
} catch let error as NSError {
// failure
print("Fetch failed: \(error.localizedDescription)")
}
}
}
Mv信标类别为NSManagedObject
import UIKit
import CoreData
class Beacons: NSManagedObject {
dynamic var major : NSNumber = 0.0
dynamic var minor : NSNumber = 0.0
dynamic var name : NSString = ""
dynamic var uuid : NSString = ""
}
但这是一个错误
let existingBeacon: Beacons = try context.executeFetchRequest(request)
无法将类型['Any Object']的值转换为指定的类型'Beacons'
请帮帮我
谢谢:)两个问题:
始终返回对象的数组executeFetchRequest
- 你必须用这种字体
无法转换类型为的值。。。到指定的类型。。。这意味着编译器通常需要通过强制转换类型来获得帮助,或者根本没有关系 PS:建议以单数形式命名核心数据实体,以避免混淆
let existingBeacons = try context.executeFetchRequest(request) as! [Beacons]