Énumération de magasins
Mise à jour : novembre 2007
Vous pouvez énumérer tous les magasins isolés pour l'utilisateur actuel à l'aide de la méthode statique GetEnumeratorde IsolatedStorageFile. GetEnumerator accepte une valeur IsolatedStorageScope et retourne un énumérateur IsolatedStorageFile. User est la seule valeur prise en charge pour IsolatedStorageScope. Pour énumérer des magasins, vous devez avoir l'autorisation IsolatedStorageFilePermission dont la valeur IsolatedStorageContainment est AdministerIsolatedStorageByUser. Lorsque la méthode GetEnumerator est appelée alors que la valeur User a été donnée à IsolatedStorageScope, elle retourne un tableau de fichiers IsolatedStorageFiles définis pour l'utilisateur en cours.
EnumeratingStores, exemple
L'exemple de code suivant obtient un magasin isolé par utilisateur et par assembly et crée quelques fichiers. La méthode GetEnumerator est appelée et le résultat est placé dans un IEnumerator. Le code parcourt ensuite IEnumerator en additionnant les tailles de fichiers, et rapporte le résultat à la console. L'énumération réelle se produit dans la méthode EnumerateTheStore privée, séparée du reste du code au bas du fichier pour plus de précision.
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;
}
}