Gets or sets a value indicating whether the dialog box allows multiple files to be selected.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
Public Property Multiselect As Boolean
public bool Multiselect { get; set; }
public: property bool Multiselect { bool get (); void set (bool value); }
member Multiselect : bool with get, set
Property Value
Type: System.Booleantrue if the dialog box allows multiple files to be selected together or concurrently; otherwise, false. The default value is false.
Use the FileNames property to access the full list of selected file names.
The following code example allows the user to select a number of images and display them in PictureBox controls on a Form. It demonstrates initializing an OpenFileDialog, setting the Title and Filter properties, and allowing the user to select multiple files by setting the Multiselect property to true. This code example assumes that your form already has an OpenFileDialog control named openFileDialog1, a Button named SelectFileButton, and a FlowLayoutPanel named flowLayoutPanel1.
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
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); } } }
.NET Framework
Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0.NET Framework Client Profile
Supported in: 4, 3.5 SP1Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.