我正在 swift 3.0 中开发一个项目,其中我有一个带有多个选择选项的 UITableView (每行都有一个 URL)。因此,在 UITableView 之上,用户可以在 UITextfield 中输入名称。我的要求是,一旦选择了这些行,数据应保存在 Coredata 中键入的名称下。截至目前,数据已保存为单独的元素,因此我无法在其名称下聚类数据。我怎么能做到这一点???。我保存和提取数据的方法如下。
保存
public static func savePlaylistDetails(audio:AudioDetails, playListName: String) {
let appDelegate = UIApplication.shared.delegate as! AppDelegate
let context = appDelegate.persistentContainer.viewContext
let newPlaylist = NSEntityDescription.insertNewObject(forEntityName: PlayList_DETAILS_ENTITY, into: context)
newPlaylist.setValue(playListName, forKey:"playlistName");
newPlaylist.setValue(audio.mediaId, forKey:"trackID");
do{
try context.save();
print("Saved.....")
}
catch{
print("There was an error")
}
}
获取保存的数据
public static func getPlayList() -> [PlayListDetails]?{
let appDelegate = UIApplication.shared.delegate as! AppDelegate;
let context = appDelegate.persistentContainer.viewContext;
let request = NSFetchRequest<NSFetchRequestResult>(entityName: PlayList_DETAILS_ENTITY)
request.returnsObjectsAsFaults = false
do{
let results = try context.fetch(request)
if(results.count > 0 ){
for result in results as! [NSManagedObject]{
let playListDetailslayListDetails? = result as? PlayListDetails
print("Title: \(playListDetails?.playlistName)")
}
return results as? [PlayListDetails]
}else{
print("No results")
}
}catch{
print("Error in fetching items")
}
return nil;
}
Best Answer-推荐答案 strong>
创建一个字典并使用正确的键将所有字段保存在字典中。然后将dict转换为数据并保存在coreData中
正在保存..
let data = NSKeyedArchiver.archivedData(withRootObject: dictionary)
let appDelegate = UIApplication.shared.delegate as! AppDelegate
let context = appDelegate.persistentContainer.viewContext
let newPlaylist = NSEntityDescription.insertNewObject(forEntityName: PlayList_DETAILS_ENTITY, into: context)
newPlaylist.setValue(data , forKey:"playlistData");
检索
先从CoreData中获取数据,再转成Dictionary。
let unarchivedDictionary = NSKeyedUnarchiver.unarchiveObject(with: data)
关于ios - 以一个名称将多个对象保存到 coredata,我们在Stack Overflow上找到一个类似的问题:
https://stackoverflow.com/questions/43840890/
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