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Vorgehensweise: Suchen von vorhandenen Dateien und Verzeichnissen im isolierten Speicher

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Um ein Verzeichnis im isolierten Speicher zu suchen, verwenden Sie die IsolatedStorageFile.GetDirectoryNames-Methode. Diese Methode akzeptiert eine Zeichenfolge, die ein Suchmuster darstellt. Sie können Platzhalterzeichen für einzelne Zeichen (?) und mehrere Zeichen (*) im Suchmuster verwenden, aber die Platzhalterzeichen müssen im letzten Teil des Namens angezeigt werden. Beispielsweise ist directory1/*ect* eine gültige Suchzeichenfolge, *ect*/directory2 aber nicht.

Um eine Datei zu suchen, verwenden Sie die IsolatedStorageFile.GetFileNames-Methode. Die für GetDirectoryNames geltende Einschränkung für Platzhalterzeichen in Suchzeichenfolgen gilt auch für GetFileNames.

Keine dieser Methoden ist rekursiv; die IsolatedStorageFile-Klasse stellt keine Methoden für das Auflisten aller Verzeichnisse oder Dateien in Ihrem Speicher bereit. Allerdings werden rekursive Methoden im folgenden Codebeispiel gezeigt.

Beispiel

Das folgende Codebeispiel zeigt das Erstellen von Dateien und Verzeichnissen in einem isolierten Speicher. Zunächst wird ein für Benutzer, Domäne und Assembly isolierter Speicher abgerufen und in der isoStore-Variablen platziert. Mit der CreateDirectory-Methode werden ein paar andere Verzeichnisse eingerichtet, und der IsolatedStorageFileStream(String, FileMode, IsolatedStorageFile)-Konstruktor erstellt einige Dateien in diesen Verzeichnissen. Der Code durchläuft dann die Ergebnisse der GetAllDirectories-Methode. Diese Methode sucht mit GetDirectoryNames alle Verzeichnisnamen im aktuellen Verzeichnis. Diese Namen werden in einem Array gespeichert, und dann ruft GetAllDirectories sich selbst auf und übergibt jedes gefundene Verzeichnis. Als Ergebnis werden alle Verzeichnisnamen in einem Array zurückgegeben. Als Nächstes ruft der Code die GetAllFiles-Methode auf. Diese Methode ruft GetAllDirectories auf, um die Namen aller Verzeichnisse zu ermitteln, und prüft dann jedes Verzeichnis mithilfe der GetFileNames-Methode auf Dateien. Das Ergebnis wird in einem Array für die Anzeige zurückgegeben.

using namespace System;
using namespace System::IO;
using namespace System::IO::IsolatedStorage;
using namespace System::Collections;
using namespace System::Collections::Generic;

public class FindingExistingFilesAndDirectories
{
public:
    // Retrieves an array of all directories in the store, and
    // displays the results.
    static void Main()
    {
        // This part of the code sets up a few directories and files in the
        // store.
        IsolatedStorageFile^ isoStore = IsolatedStorageFile::GetStore(IsolatedStorageScope::User |
            IsolatedStorageScope::Assembly, (Type ^)nullptr, (Type ^)nullptr);
        isoStore->CreateDirectory("TopLevelDirectory");
        isoStore->CreateDirectory("TopLevelDirectory/SecondLevel");
        isoStore->CreateDirectory("AnotherTopLevelDirectory/InsideDirectory");
        gcnew IsolatedStorageFileStream("InTheRoot.txt", FileMode::Create, isoStore);
        gcnew IsolatedStorageFileStream("AnotherTopLevelDirectory/InsideDirectory/HereIAm.txt",
            FileMode::Create, isoStore);
        // End of setup.

        Console::WriteLine('\r');
        Console::WriteLine("Here is a list of all directories in this isolated store:");

        for each (String^ directory in GetAllDirectories("*", isoStore))
        {
            Console::WriteLine(directory);
        }
        Console::WriteLine('\r');

        // Retrieve all the files in the directory by calling the GetFiles
        // method.

        Console::WriteLine("Here is a list of all the files in this isolated store:");
        for each (String^ file in GetAllFiles("*", isoStore))
        {
            Console::WriteLine(file);
        }

    } // End of Main.

    // Method to retrieve all directories, recursively, within a store.
    static List<String^>^ GetAllDirectories(String^ pattern, IsolatedStorageFile^ storeFile)
    {
        // Get the root of the search string.
        String^ root = Path::GetDirectoryName(pattern);

        if (root != "")
        {
            root += "/";
        }

        // Retrieve directories.
        array<String^>^ directories = storeFile->GetDirectoryNames(pattern);

        List<String^>^ directoryList = gcnew List<String^>(directories);

        // Retrieve subdirectories of matches.
        for (int i = 0, max = directories->Length; i < max; i++)
        {
             String^ directory = directoryList[i] + "/";
             List<String^>^ more = GetAllDirectories (root + directory + "*", storeFile);

             // For each subdirectory found, add in the base path.
             for (int j = 0; j < more->Count; j++)
             {
                 more[j] = directory + more[j];
             }

            // Insert the subdirectories into the list and
            // update the counter and upper bound.
            directoryList->InsertRange(i + 1, more);
            i += more->Count;
            max += more->Count;
        }

        return directoryList;
    }

    static List<String^>^ GetAllFiles(String^ pattern, IsolatedStorageFile^ storeFile)
    {
        // Get the root and file portions of the search string.
        String^ fileString = Path::GetFileName(pattern);
        array<String^>^ files = storeFile->GetFileNames(pattern);

        List<String^>^ fileList = gcnew List<String^>(files);

        // Loop through the subdirectories, collect matches,
        // and make separators consistent.
        for each (String^ directory in GetAllDirectories( "*", storeFile))
        {
            for each (String^ file in storeFile->GetFileNames(directory + "/" + fileString))
            {
                fileList->Add((directory + "/" + file));
            }
        }

        return fileList;
    } // End of GetFiles.
};

int main()
{
    FindingExistingFilesAndDirectories::Main();
}

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

public class FindingExistingFilesAndDirectories
{
    // Retrieves an array of all directories in the store, and
    // displays the results.
    public static void Main()
    {
        // This part of the code sets up a few directories and files in the
        // store.
        IsolatedStorageFile isoStore = IsolatedStorageFile.GetStore(IsolatedStorageScope.User |
            IsolatedStorageScope.Assembly, null, null);
        isoStore.CreateDirectory("TopLevelDirectory");
        isoStore.CreateDirectory("TopLevelDirectory/SecondLevel");
        isoStore.CreateDirectory("AnotherTopLevelDirectory/InsideDirectory");
        isoStore.CreateFile("InTheRoot.txt");
        isoStore.CreateFile("AnotherTopLevelDirectory/InsideDirectory/HereIAm.txt");
        // End of setup.

        Console.WriteLine('\r');
        Console.WriteLine("Here is a list of all directories in this isolated store:");

        foreach (string directory in GetAllDirectories("*", isoStore))
        {
            Console.WriteLine(directory);
        }
        Console.WriteLine('\r');

        // Retrieve all the files in the directory by calling the GetFiles
        // method.

        Console.WriteLine("Here is a list of all the files in this isolated store:");
        foreach (string file in GetAllFiles("*", isoStore)){
            Console.WriteLine(file);
        }
    } // End of Main.

    // Method to retrieve all directories, recursively, within a store.
    public static List<String> GetAllDirectories(string pattern, IsolatedStorageFile storeFile)
    {
        // Get the root of the search string.
        string root = Path.GetDirectoryName(pattern);

        if (root != "")
        {
            root += "/";
        }

        // Retrieve directories.
        List<String> directoryList = new List<String>(storeFile.GetDirectoryNames(pattern));

        // Retrieve subdirectories of matches.
        for (int i = 0, max = directoryList.Count; i < max; i++)
        {
            string directory = directoryList[i] + "/";
            List<String> more = GetAllDirectories(root + directory + "*", storeFile);

            // For each subdirectory found, add in the base path.
            for (int j = 0; j < more.Count; j++)
            {
                more[j] = directory + more[j];
            }

            // Insert the subdirectories into the list and
            // update the counter and upper bound.
            directoryList.InsertRange(i + 1, more);
            i += more.Count;
            max += more.Count;
        }

        return directoryList;
    }

    public static List<String> GetAllFiles(string pattern, IsolatedStorageFile storeFile)
    {
        // Get the root and file portions of the search string.
        string fileString = Path.GetFileName(pattern);

        List<String> fileList = new List<String>(storeFile.GetFileNames(pattern));

        // Loop through the subdirectories, collect matches,
        // and make separators consistent.
        foreach (string directory in GetAllDirectories("*", storeFile))
        {
            foreach (string file in storeFile.GetFileNames(directory + "/" + fileString))
            {
                fileList.Add((directory + "/" + file));
            }
        }

        return fileList;
    } // End of GetFiles.
}

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

Public class FindingExistingFilesAndDirectories
    ' These arrayLists hold the directory and file names as they are found.

    Private Shared directoryList As New List(Of String)
    Private Shared fileList As New List(Of String)

    ' Retrieves an array of all directories in the store, and
    ' displays the results.

    Public Shared Sub Main()
        ' This part of the code sets up a few directories and files in the store.
        Dim isoStore As IsolatedStorageFile = IsolatedStorageFile.GetStore(IsolatedStorageScope.User Or _
            IsolatedStorageScope.Assembly Or IsolatedStorageScope.Domain, Nothing, Nothing)
        isoStore.CreateDirectory("TopLevelDirectory")
        isoStore.CreateDirectory("TopLevelDirectory/SecondLevel")
        isoStore.CreateDirectory("AnotherTopLevelDirectory/InsideDirectory")
        isoStore.CreateFile("InTheRoot.txt")
        isoStore.CreateFile("AnotherTopLevelDirectory/InsideDirectory/HereIAm.txt")
        ' End of setup.

        Console.WriteLine()
        Console.WriteLine("Here is a list of all directories in this isolated store:")

        GetAllDirectories("*", isoStore)
        For Each directory As String In directoryList
            Console.WriteLine(directory)
        Next

        Console.WriteLine()
        Console.WriteLine("Retrieve all the files in the directory by calling the GetFiles method.")

        GetAllFiles(isoStore)
        For Each file As String In fileList
            Console.WriteLine(file)
        Next
    End Sub

    Public Shared Sub GetAllDirectories(ByVal pattern As String, ByVal storeFile As IsolatedStorageFile)
        ' Retrieve directories.
        Dim directories As String() = storeFile.GetDirectoryNames(pattern)

        For Each directory As String In directories
            ' Add the directory to the final list.
            directoryList.Add((pattern.TrimEnd(CChar("*"))) + directory + "/")
            ' Call the method again using directory.
            GetAllDirectories((pattern.TrimEnd(CChar("*")) + directory + "/*"), storeFile)
        Next
    End Sub

    Public Shared Sub GetAllFiles(ByVal storefile As IsolatedStorageFile)
        ' This adds the root to the directory list.
        directoryList.Add("*")
        For Each directory As String In directoryList
            Dim files As String() = storefile.GetFileNames(directory + "*")
            For Each dirfile As String In files
                fileList.Add(dirfile)
            Next
        Next
    End Sub
End Class

Siehe auch