OpenFileDialog.Multiselect Eigenschaft

Definition

Ruft einen Wert ab, der angibt, ob im Dialogfeld mehrere Dateien ausgewählt werden können, oder legt diesen fest.

public:
 property bool Multiselect { bool get(); void set(bool value); };
public bool Multiselect { get; set; }
member this.Multiselect : bool with get, set
Public Property Multiselect As Boolean

Eigenschaftswert

Boolean

true, wenn im Dialogfeld mehrere Dateien zusammen oder gleichzeitig ausgewählt werden können, andernfalls false. Der Standardwert ist false.

Beispiele

Im folgenden Codebeispiel kann der Benutzer eine Reihe von Bildern auswählen und diese in Steuerelementen in PictureBox einem Formular anzeigen. Es veranschaulicht das Initialisieren einer OpenFileDialog, das Festlegen der Title Eigenschaften und und Filter das Zulassen, dass der Benutzer mehrere Dateien auswählen kann, indem die Multiselect Eigenschaft auf true festgelegt wird. In diesem Codebeispiel wird davon ausgegangen, dass Ihr Formular bereits über ein OpenFileDialog Steuerelement mit dem Namen openFileDialog1, ein Button benanntes SelectFileButtonund ein FlowLayoutPanel mit dem Namen verfügt flowLayoutPanel1.

private void Form1_Load(object sender, EventArgs e)
{
    InitializeOpenFileDialog();
}

private void InitializeOpenFileDialog()
{
    // Set the file dialog to filter for graphics files.
    this.openFileDialog1.Filter =
        "Images (*.BMP;*.JPG;*.GIF)|*.BMP;*.JPG;*.GIF|" +
        "All files (*.*)|*.*";

    // Allow the user to select multiple images.
    this.openFileDialog1.Multiselect = true;
    this.openFileDialog1.Title = "My Image Browser";
}

private void selectFilesButton_Click(object sender, EventArgs e)
{
    DialogResult dr = this.openFileDialog1.ShowDialog();
    if (dr == System.Windows.Forms.DialogResult.OK)
    {
        // Read the files
        foreach (String file in openFileDialog1.FileNames) 
        {
            // Create a PictureBox.
            try
            {
                PictureBox pb = new PictureBox();
                Image loadedImage = Image.FromFile(file);
                pb.Height = loadedImage.Height;
                pb.Width = loadedImage.Width;
                pb.Image = loadedImage;
                flowLayoutPanel1.Controls.Add(pb);
            }
            catch (SecurityException ex)
            {
                // The user lacks appropriate permissions to read files, discover paths, etc.
                MessageBox.Show("Security error. Please contact your administrator for details.\n\n" +
                    "Error message: " + ex.Message + "\n\n" +
                    "Details (send to Support):\n\n" + ex.StackTrace
                );
            }
            catch (Exception ex)
            {
                // Could not load the image - probably related to Windows file system permissions.
                MessageBox.Show("Cannot display the image: " + file.Substring(file.LastIndexOf('\\'))
                    + ". You may not have permission to read the file, or " +
                    "it may be corrupt.\n\nReported error: " + ex.Message);
            }
        }
    }
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    InitializeOpenFileDialog()
End Sub

Private Sub SelectFileButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles SelectFileButton.Click
    Dim dr As DialogResult = Me.OpenFileDialog1.ShowDialog()
    If (dr = System.Windows.Forms.DialogResult.OK) Then
        ' Read the files
        Dim file As String
        For Each file In OpenFileDialog1.FileNames
            ' Create a PictureBox for each file, and add that file to the FlowLayoutPanel.
            Try
                Dim pb As New PictureBox()
                Dim loadedImage As Image = Image.FromFile(file)
                pb.Height = loadedImage.Height
                pb.Width = loadedImage.Width
                pb.Image = loadedImage
                FlowLayoutPanel1.Controls.Add(pb)
            Catch SecEx As SecurityException
                ' The user lacks appropriate permissions to read files, discover paths, etc.
                MessageBox.Show("Security error. Please contact your administrator for details.\n\n" & _
                    "Error message: " & SecEx.Message & "\n\n" & _
                    "Details (send to Support):\n\n" & SecEx.StackTrace)
            Catch ex As Exception
                ' Could not load the image - probably permissions-related.
                MessageBox.Show(("Cannot display the image: " & file.Substring(file.LastIndexOf("\"c)) & _
                ". You may not have permission to read the file, or " + "it may be corrupt." _
                & ControlChars.Lf & ControlChars.Lf & "Reported error: " & ex.Message))
            End Try
        Next file
    End If
End Sub

Public Sub InitializeOpenFileDialog()
    ' Set the file dialog to filter for graphics files.
    Me.OpenFileDialog1.Filter = _
            "Images (*.BMP;*.JPG;*.GIF)|*.BMP;*.JPG;*.GIF|" + _
            "All files (*.*)|*.*"

    ' Allow the user to select multiple images.
    Me.OpenFileDialog1.Multiselect = True
    Me.OpenFileDialog1.Title = "My Image Browser"
End Sub

Hinweise

Verwenden Sie die FileNames -Eigenschaft, um auf die vollständige Liste der ausgewählten Dateinamen zuzugreifen.

Gilt für

Siehe auch