Cómo: Enumerar almacenes para el almacenamiento aislado

Se puede enumerar todos los almacenes aislados del usuario actual usando el método estático de GetEnumerator de IsolatedStorageFile. GetEnumerator toma un valor IsolatedStorageScope y devuelve un enumerador IsolatedStorageFile. User es el único valor de IsolatedStorageScope admitido. Para enumerar almacenes se debe tener el IsolatedStorageFilePermission que especifica el valor IsolatedStorageContainmentAdministerIsolatedStorageByUser. Cuando se le llama con el valor User de IsolatedStorageScope, GetEnumerator devuelve una matriz de IsolatedStorageFiles definidos para el usuario actual.

Ejemplo de EnumeratingStores

El siguiente código de ejemplo obtiene un almacén aislado por usuario y ensamblado y crea unos cuantos archivos. Se llama al método GetEnumerator y el resultado se coloca en una interfaz IEnumerator. A continuación, el código recorre el IEnumerator, suma los tamaños de los archivos e informa del resultado en la consola. La enumeración tiene lugar en el método privado EnumerateTheStore que se separa del resto del código al final del archivo para una mayor claridad.

Imports System
Imports System.IO
Imports System.IO.IsolatedStorage
Imports System.Collections

Public Module modmain

    Sub Main()

        ' Get an isolated store for this assembly and put it into an
        ' IsolatedStorageFile object.

        Dim isoStore As IsolatedStorageFile
        isoStore = IsolatedStorageFile.GetStore(IsolatedStorageScope.User Or IsolatedStorageScope.Assembly Or IsolatedStorageScope.Domain, Nothing, Nothing)

        ' This code creates a few files so that they can be enumerated.

        Dim FileA As IsolatedStorageFileStream
        FileA = New IsolatedStorageFileStream("TestFileA.Txt", FileMode.Create, isoStore)
        Dim FileB As IsolatedStorageFileStream
        FileB = New IsolatedStorageFileStream("TestFileB.Txt", FileMode.Create, isoStore)
        Dim FileC As IsolatedStorageFileStream
        FileC = New IsolatedStorageFileStream("TestFileC.Txt", FileMode.Create, isoStore)
        Dim FileD As IsolatedStorageFileStream
        FileD = New IsolatedStorageFileStream("TestFileD.Txt", FileMode.Create, isoStore)

        FileA.Close()
        FileB.Close()
        FileC.Close()
        FileD.Close()

        ' There might be a small delay between when the above code
        ' executes and when the files are created in the store. 
        ' Closing and opening the store in this example ensures that
        ' the common language runtime has finished creating the files.

        isoStore.Close()
        isoStore = IsolatedStorageFile.GetStore(IsolatedStorageScope.User Or IsolatedStorageScope.Assembly, Nothing, Nothing)


        ' This line of code calls a method at the bottom of the program
        ' that puts all the files in isoStore into an IEnumerator.

        Dim allFiles As IEnumerator
        allFiles = EnumerateTheStore(isoStore)

        Dim totalSize As Long

        ' This code counts up the sizes of all the stores.

        While (allFiles.MoveNext())
            Dim store As IsolatedStorageFile

            ' Explicity convert the current object in allFiles
            ' into an IsolatedStorageFile.

            store = CType(allFiles.Current, IsolatedStorageFile)

            ' Find the current size of the IsolatedStorageFile as
            ' an UInt64, and convert that to a string. Get the value
            ' of the string as a double and convert that to a Long.

            totalSize += CLng(Val(store.CurrentSize.ToString))

        End While

        ' Print out the value.

        System.Console.WriteLine("The size of all the isolated stores in the user scope = " + totalSize.ToString)

    End Sub

    Function EnumerateTheStore(ByVal isoStore As IsolatedStorageFile) As IEnumerator

        Return isoStore.GetEnumerator(IsolatedStorageScope.User)

    End Function
End Module

using System;
using System.IO;
using System.IO.IsolatedStorage;
using System.Collections;

public class EnumeratingStores{

    public static int Main(){

        // Get an isolated store for this assembly and put it into an
        // IsolatedStorageFile object.

        IsolatedStorageFile isoStore =  IsolatedStorageFile.GetStore(IsolatedStorageScope.User | IsolatedStorageScope.Assembly, null, null);

        // This code creates a few files so that they can be enumerated.

        IsolatedStorageFileStream streamA = new IsolatedStorageFileStream("TestFileA.Txt", FileMode.Create, isoStore);
        IsolatedStorageFileStream streamB = new IsolatedStorageFileStream("TestFileB.Txt", FileMode.Create, isoStore);
        IsolatedStorageFileStream streamC = new IsolatedStorageFileStream("TestFileC.Txt", FileMode.Create, isoStore);
        IsolatedStorageFileStream streamD = new IsolatedStorageFileStream("TestFileD.Txt", FileMode.Create, isoStore);

        streamA.Close();
        streamB.Close();
        streamC.Close();
        streamD.Close();

        // There might be a small delay between when the above code
        // executes and when the files are created in the store. 
        // Closing and opening the store in this example ensures that
        // the common language runtime has finished creating the files.
        isoStore .Close();
        isoStore =  IsolatedStorageFile.GetStore(IsolatedStorageScope.User | IsolatedStorageScope.Assembly, null, null);
        
        
        // This line of code calls a method at the bottom of the program
        // that puts all the files in isoStore into an IEnumerator.

        IEnumerator allFiles = EnumerateTheStore (isoStore);
        long totalsize = 0;

        // This code counts up the sizes of all the stores.

        while(allFiles .MoveNext()){
            IsolatedStorageFile store = (IsolatedStorageFile)allFiles.Current;
            totalsize += (long)store.CurrentSize;
        }

        Console.WriteLine("The total size = "+totalsize);
        return 0;
    }

    // This method returns an IEnucontaining all the files for a user.

    private static IEnumerator EnumerateTheStore(IsolatedStorageFile isoStore){
      
        IEnumerator e = IsolatedStorageFile.GetEnumerator(IsolatedStorageScope.User);
        
        return e;
    }
}

Vea también

Referencia

IsolatedStorageFile

Otros recursos

Realizar tareas de almacenamiento aislado