Swiftについての覚書４

CoreDataの操作について

読み込み、追加、更新、削除のサンプルです。
import CoreData を忘れないようにしてください。

読み込み

    let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
    let fetchRequest = NSFetchRequest(entityName: "CoreDataTest")
    var coreData:[CoreDataTest] = []
    // 読み込み
    do {
        coreData = try appDelegate.managedObjectContext.executeFetchRequest(fetchRequest) as! [CoreDataTest]
    } catch let error as NSError {
        print(error)
    }

追加

    let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate

    let coreData = NSEntityDescription.insertNewObjectForEntityForName("CoreDataTest", inManagedObjectContext: appDelegate.managedObjectContext) as! CoreDataTest
    coreData.id = 1
    coreData.name = "コアデータ"

    // コミット
    appDelegate.saveContext()

更新

    let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
    let fetchRequest = NSFetchRequest(entityName: "CoreDataTest")

    do {
        let coreData = try appDelegate.managedObjectContext.executeFetchRequest(fetchRequest) as! [CoreDataTest]
        for data in coreData {
            data.id = 2
            data.name = "新コアデータ"
        }
    } catch let error as NSError {
        print(error)
    }

    // コミット
    appDelegate.saveContext()

削除

    let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
    let fetchRequest = NSFetchRequest(entityName: "CoreDataTest")

    do {
        let coreData = try appDelegate.managedObjectContext.executeFetchRequest(fetchRequest) as! [CoreDataTest]
        for data in coreData {
            appDelegate.managedObjectContext.deleteObject(data)
        }
    } catch let error as NSError {
        print(error)
    }

    // コミット
    appDelegate.saveContext()