iOS CoreData简单入门 － Swift版
CoreData －－－ Swift
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
// Saves changes in the application's managed object context before the application terminates.
self.saveContext()
}
// MARK: - Core Data stack
lazy var applicationDocumentsDirectory: NSURL = {
// The directory the application uses to store the Core Data store file. This code uses a directory named "com.scorpio.CoreDataDemo" in the application's documents Application Support directory.
let urls = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
return urls[urls.count-1] as! NSURL
}()
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("CoreDataDemo", 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("CoreDataDemo.sqlite")
println("sql路径:\(url)")
var error: NSError? = nil
var failureReason = "There was an error creating or loading the application's saved data."
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
}()
// MARK: - Core Data Saving support
func saveContext () {
if let moc = self.managedObjectContext {
var error: NSError? = nil
if moc.hasChanges && !moc.save(&error) {
// Replace this implementation 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()
}
}
}
4这时可以再ViewController里添加代码
var context = (UIApplication.sharedApplication().delegate as! AppDelegate).managedObjectContext ／／获取NSManagedObjectContext
// 添加数据
var info :AnyObject = NSEntityDescription.insertNewObjectForEntityForName("User", inManagedObjectContext: context!) ／／获取之前所创建的Entity
// 设置数据
info.setValue(name, forKey: "name”)
info.setValue(age, forKey: “year”)
info.setValue(id, forKey: "id")
context.save(nil) // 最后保存数据
这时候可以把 AppDelegate 中 let url = self.applicationDocumentsDirectory.URLByAppendingPathComponent("CoreDataDemo.sqlite”)
打印 url，并根据url显示路径 可以查看sqlite数据库 ，用sqlite 管理工具打开，就可以看到添加的数据了
5，下面是查找，更改，删除 数据的方法 ，感兴趣的可以一一试试
查找
var f = NSFetchRequest(entityName: "User")
var：dataArr = context.executeFetchRequest(f , error: nil)!
data.setValue(tfName.text, forKey: "name")
data.setValue(tfAge.text.toInt(), forKey: "year")
data.managedObjectContext?.save(nil) // 保存对象
context.deleteObject(dataArr[indexPath.row] as! NSManagedObject)
context.save(nil)
其中 data 是 NSManagedObject类型数据
context 是NSManagedObjectContext 实例化
添加，更改，删除操作时候会涉及保存操作
