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One way to persist objects in isolated storage

In unele cazuri avem nevoie sa stocam date in isolated storage. In cazul in care numarul de date pe vrem sa le stocam nu este foarte mare, putem sa le serializam direct si sa le salvam sub forma unui fisier in isolated storage.
In exemplul de mai jos, datele le-am serializat folosind DataContractSerializer. Din aceasta cauta, clasele pe care vrem sa le salvam trebuie sa fie decorate cu atributul DataContract, iar fiecare proprietate pe care dorim sa o salvam trebuie decorata cu atributul DataMember.
[DataContract]
class Foo
{
   [DataMember]
   public string Name { get; set; }
   public int Age {get; set; }
}
In exemplul dat mai sus o sa salvam doar proprietatea Name.
Mai jos puteti sa gasiti o clasa generica care salveaza un obiect dat. In metodele Save si Load as fi putut sa trimit ca si parametru numele la fisier, dar am ales ca numele de fisier sa se genereze pe baza tipului. Se poate si in alte moduri.
public class IsolatedStorageRepository<TItem>
   {
       public void Save(TItem item)
       {
           using (IsolatedStorageFileStream fileStream = IsolatedStorageFile.GetUserStoreForApplication()
                                                           .OpenFile(GetFileName(), FileMode.Create))
           {
               new DataContractSerializer(typeof(TItem))
                       .WriteObject(fileStream, item);
           }
       }
       public TItem Load()
       {
           IsolatedStorageFile storageFile = IsolatedStorageFile.GetUserStoreForApplication();
           if (!storageFile.FileExists(filename))
           {
               return default(TItem);
           }

           using (IsolatedStorageFileStream fileStream = storageFile.OpenFile(GetFileName, FileMode.Open))
           {
               return (TItem)new DataContractSerializer(typeof(TItem)).ReadObject(fileStream);              
           }
       }

       private string GetFileName()
       {
           string typeName = typeof (TItem).ToGenericFullName();
           typeName = typeName.Replace('<', '_');
           typeName = typeName.Replace('>', '_');

           return typeName;
       }
   }
Metoda ToGenericFullName imi returneaza numele unui obiect. Pentru a vedea implementarea acestei clase puteti sa intrati pe link-ul urmator: http://vunvulearadu.blogspot.com/2012/03/how-to-get-friendly-format-for.html
List<Foo> fooList = new List<Foo>();
// populate list
IsolatedStorageRepository repository = new IsolatedStorageRepository<List<Foo>>();
// Save list
repository.Save(fooList);
// Load list
repository.Load();
Solutia se poate implementa in diferite moduri. Aceasta este doar o varianta.
Enjoy!.

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