Question

错误出现在我用//

标记的两行上

第一个错误是 - extra argument 'error' in call

第二个错误是 - argument passed to that call takes no arguments

import UIKit
import CoreData

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    lazy var applicationDocumentsDirectory: NSURL = {
        // The directory the application uses to store the Core Data store file. This code uses a directory named "com.ShreyasPapinwar.Shreyas_Papinwar" in the application's documents Application Support directory.
        let urls = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
        return urls[urls.count-1] 
    }()

    lazy var managedObjectModel: NSManagedObjectModel = {
        // The managed object model for the application. This property is not optional. It is a fatal error for the application not to be able to find and load its model.
        let modelURL = NSBundle.mainBundle().URLForResource("Shreyas_Papinwar", withExtension: "momd")!
        return NSManagedObjectModel(contentsOfURL: modelURL)!
    }()

    lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator? = {
        // The persistent store coordinator for the application. This implementation creates and return a coordinator, having added the store for the application to it. This property is optional since there are legitimate error conditions that could cause the creation of the store to fail.
        // Create the coordinator and store
        var coordinator: NSPersistentStoreCoordinator? = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
        let url = self.applicationDocumentsDirectory.URLByAppendingPathComponent("Shreyas_Papinwar.sqlite")
        var error: NSError? = nil
        var failureReason = "There was an error creating or loading the application's saved data."

// -------> this line has error - extra argument error in call
        if coordinator!.addPersistentStoreWithType(NSSQLiteStoreType, configuration: nil, URL: url, options: nil, error: &error) == nil {
            coordinator = nil
            // Report any error we got.
            var dict = [String: AnyObject]()
            dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data"
            dict[NSLocalizedFailureReasonErrorKey] = failureReason
            dict[NSUnderlyingErrorKey] = error
            error = NSError(domain: "YOUR_ERROR_DOMAIN", code: 9999, userInfo: dict)
            // Replace this with code to handle the error appropriately.
            // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
            NSLog("Unresolved error \(error), \(error!.userInfo)")
            abort()
        }

        return coordinator
    }()

    lazy var managedObjectContext: NSManagedObjectContext? = {
        // Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.) This property is optional since there are legitimate error conditions that could cause the creation of the context to fail.
        let coordinator = self.persistentStoreCoordinator
        if coordinator == nil {
            return nil
        }
        var managedObjectContext = NSManagedObjectContext()
        managedObjectContext.persistentStoreCoordinator = coordinator
        return managedObjectContext
    }()

}

Answer 1

解决此问题的最简单方法：

在Xcode 7 / Swift 2
将示例项目中的Core Data堆栈代码复制并粘贴到您的项目中 Swift 2中还有一些更改。
调整文件名，数据型号名称和其他自定义设置。

尽管如此 - 正如luk2302建议的那样 - 阅读文档！

Answer 2

来自Apple的文档：

func addPersistentStoreWithType(_ storeType: String,
                  configuration configuration: String?,
                            URL storeURL: NSURL?,
                        options options: [NSObject : AnyObject]?) throws -> NSPersistentStore

含义 - ＆gt;此函数的签名在其末尾没有错误参数！如果出现错误，则会抛出异常：

来自文档：

处理SWIFT中的错误：在Swift中，此方法返回一个非可选结果，并使用throws关键字标记，以指示在失败的情况下它会引发错误。

传递给不带参数的调用的参数 - AppDelegate中的错误

2 个答案: