FolderBrowserDialog Constructor

Reference

Definition

Namespace:: System.Windows.Forms

Assembly:: System.Windows.Forms.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Initializes a new instance of the FolderBrowserDialog class.

public:
 FolderBrowserDialog();

public FolderBrowserDialog ();

Public Sub New ()

Examples

The following code example creates an application that enables the user to open rich text (.rtf) files within the RichTextBox control.

// The following example displays an application that provides the ability to
// open rich text files (rtf) into the RichTextBox. The example demonstrates
// using the FolderBrowserDialog to set the default directory for opening files.
// The OpenFileDialog is used to open the file.
#using <System.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::IO;
public ref class FolderBrowserDialogExampleForm: public System::Windows::Forms::Form
{
private:
   FolderBrowserDialog^ folderBrowserDialog1;
   OpenFileDialog^ openFileDialog1;
   RichTextBox^ richTextBox1;
   MainMenu^ mainMenu1;
   MenuItem^ fileMenuItem;
   MenuItem^ openMenuItem;
   MenuItem^ folderMenuItem;
   MenuItem^ closeMenuItem;
   String^ openFileName;
   String^ folderName;
   bool fileOpened;

public:

   // Constructor.
   FolderBrowserDialogExampleForm()
   {
      fileOpened = false;
      this->mainMenu1 = gcnew System::Windows::Forms::MainMenu;
      this->fileMenuItem = gcnew System::Windows::Forms::MenuItem;
      this->openMenuItem = gcnew System::Windows::Forms::MenuItem;
      this->folderMenuItem = gcnew System::Windows::Forms::MenuItem;
      this->closeMenuItem = gcnew System::Windows::Forms::MenuItem;
      this->openFileDialog1 = gcnew System::Windows::Forms::OpenFileDialog;
      this->folderBrowserDialog1 = gcnew System::Windows::Forms::FolderBrowserDialog;
      this->richTextBox1 = gcnew System::Windows::Forms::RichTextBox;
      this->mainMenu1->MenuItems->Add( this->fileMenuItem );
      array<System::Windows::Forms::MenuItem^>^temp0 = {this->openMenuItem,this->closeMenuItem,this->folderMenuItem};
      this->fileMenuItem->MenuItems->AddRange( temp0 );
      this->fileMenuItem->Text = "File";
      this->openMenuItem->Text = "Open...";
      this->openMenuItem->Click += gcnew System::EventHandler( this, &FolderBrowserDialogExampleForm::openMenuItem_Click );
      this->folderMenuItem->Text = "Select Directory...";
      this->folderMenuItem->Click += gcnew System::EventHandler( this, &FolderBrowserDialogExampleForm::folderMenuItem_Click );
      this->closeMenuItem->Text = "Close";
      this->closeMenuItem->Click += gcnew System::EventHandler( this, &FolderBrowserDialogExampleForm::closeMenuItem_Click );
      this->closeMenuItem->Enabled = false;
      this->openFileDialog1->DefaultExt = "rtf";
      this->openFileDialog1->Filter = "rtf files (*.rtf)|*.rtf";
      
      // Set the help text description for the FolderBrowserDialog.
      this->folderBrowserDialog1->Description = "Select the directory that you want to use as the default.";
      
      // Do not allow the user to create new files via the FolderBrowserDialog.
      this->folderBrowserDialog1->ShowNewFolderButton = false;
      
      // Default to the My Documents folder.
      this->folderBrowserDialog1->RootFolder = Environment::SpecialFolder::Personal;
      this->richTextBox1->AcceptsTab = true;
      this->richTextBox1->Location = System::Drawing::Point( 8, 8 );
      this->richTextBox1->Size = System::Drawing::Size( 280, 344 );
      this->richTextBox1->Anchor = static_cast<AnchorStyles>(AnchorStyles::Top | AnchorStyles::Left | AnchorStyles::Bottom | AnchorStyles::Right);
      this->ClientSize = System::Drawing::Size( 296, 360 );
      this->Controls->Add( this->richTextBox1 );
      this->Menu = this->mainMenu1;
      this->Text = "RTF Document Browser";
   }


private:

   // Bring up a dialog to open a file.
   void openMenuItem_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      
      // If a file is not opened then set the initial directory to the
      // FolderBrowserDialog::SelectedPath value.
      if (  !fileOpened )
      {
         openFileDialog1->InitialDirectory = folderBrowserDialog1->SelectedPath;
         openFileDialog1->FileName = nullptr;
      }

      
      // Display the openFile Dialog.
      System::Windows::Forms::DialogResult result = openFileDialog1->ShowDialog();
      
      // OK button was pressed.
      if ( result == ::DialogResult::OK )
      {
         openFileName = openFileDialog1->FileName;
         try
         {
            
            // Output the requested file in richTextBox1.
            Stream^ s = openFileDialog1->OpenFile();
            richTextBox1->LoadFile( s, RichTextBoxStreamType::RichText );
            s->Close();
            fileOpened = true;
         }
         catch ( Exception^ exp ) 
         {
            MessageBox::Show( String::Concat( "An error occurred while attempting to load the file. The error is: ", System::Environment::NewLine, exp, System::Environment::NewLine ) );
            fileOpened = false;
         }

         Invalidate();
         closeMenuItem->Enabled = fileOpened;
      }
      // Cancel button was pressed.
      else
      
      // Cancel button was pressed.
      if ( result == ::DialogResult::Cancel )
      {
         return;
      }
   }


   // Close the current file.
   void closeMenuItem_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      richTextBox1->Text = "";
      fileOpened = false;
      closeMenuItem->Enabled = false;
   }


   // Bring up a dialog to chose a folder path in which to open/save a file.
   void folderMenuItem_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      
      // Show the FolderBrowserDialog.
      System::Windows::Forms::DialogResult result = folderBrowserDialog1->ShowDialog();
      if ( result == ::DialogResult::OK )
      {
         folderName = folderBrowserDialog1->SelectedPath;
         if (  !fileOpened )
         {
            
            // No file is opened, bring up openFileDialog in selected path.
            openFileDialog1->InitialDirectory = folderName;
            openFileDialog1->FileName = nullptr;
            openMenuItem->PerformClick();
         }
      }
   }

};


// The main entry point for the application.
int main()
{
   Application::Run( gcnew FolderBrowserDialogExampleForm );
}

// The following example displays an application that provides the ability to 
// open rich text files (rtf) into the RichTextBox. The example demonstrates 
// using the FolderBrowserDialog to set the default directory for opening files.
// The OpenFileDialog class is used to open the file.
using System;
using System.Drawing;
using System.Windows.Forms;
using System.IO;

public class FolderBrowserDialogExampleForm : System.Windows.Forms.Form
{
    private FolderBrowserDialog folderBrowserDialog1;
    private OpenFileDialog openFileDialog1;

    private RichTextBox richTextBox1;

    private MenuStrip mainMenu1;
    private ToolStripMenuItem fileMenuItem, openMenuItem;
    private ToolStripMenuItem folderMenuItem, closeMenuItem;

    private string openFileName, folderName;

    private bool fileOpened = false;

    // The main entry point for the application.
    [STAThreadAttribute]
    static void Main()
    {
        Application.Run(new FolderBrowserDialogExampleForm());
    }

    // Constructor.
    public FolderBrowserDialogExampleForm()
    {
        this.mainMenu1 = new MenuStrip();

        this.fileMenuItem = new ToolStripMenuItem();
        this.openMenuItem = new ToolStripMenuItem();
        this.folderMenuItem = new ToolStripMenuItem();
        this.closeMenuItem = new ToolStripMenuItem();

        this.openFileDialog1 = new OpenFileDialog();
        this.folderBrowserDialog1 = new FolderBrowserDialog();
        this.richTextBox1 = new RichTextBox();

        this.mainMenu1.Items.Add(this.fileMenuItem);

        this.fileMenuItem.Text = "File";
        this.fileMenuItem.DropDownItems.AddRange(
            new ToolStripItem[] {
                this.openMenuItem,
                this.closeMenuItem,
                this.folderMenuItem
            }
        );

        this.openMenuItem.Text = "Open...";
        this.openMenuItem.Click += new EventHandler(this.openMenuItem_Click);

        this.folderMenuItem.Text = "Select Directory...";
        this.folderMenuItem.Click += new EventHandler(this.folderMenuItem_Click);

        this.closeMenuItem.Text = "Close";
        this.closeMenuItem.Click += new EventHandler(this.closeMenuItem_Click);
        this.closeMenuItem.Enabled = false;

        this.openFileDialog1.DefaultExt = "rtf";
        this.openFileDialog1.Filter = "rtf files (*.rtf)|*.rtf";

        // Set the help text description for the FolderBrowserDialog.
        this.folderBrowserDialog1.Description =
            "Select the directory that you want to use as the default.";

        // Do not allow the user to create new files via the FolderBrowserDialog.
        this.folderBrowserDialog1.ShowNewFolderButton = false;

        // Default to the My Documents folder.
        this.folderBrowserDialog1.RootFolder = Environment.SpecialFolder.Personal;

        this.richTextBox1.AcceptsTab = true;
        this.richTextBox1.Location = new System.Drawing.Point(8, 40);
        this.richTextBox1.Size = new System.Drawing.Size(280, 312);
        this.richTextBox1.Anchor = (
            AnchorStyles.Top |
            AnchorStyles.Left |
            AnchorStyles.Bottom |
            AnchorStyles.Right
        );

        this.ClientSize = new System.Drawing.Size(296, 360);
        this.Controls.Add(this.mainMenu1);
        this.Controls.Add(this.richTextBox1);
        this.MainMenuStrip = this.mainMenu1;
        this.Text = "RTF Document Browser";
    }

    // Bring up a dialog to open a file.
    private void openMenuItem_Click(object sender, EventArgs e)
    {
        // If a file is not opened, then set the initial directory to the
        // FolderBrowserDialog.SelectedPath value.
        if (!fileOpened) {
            openFileDialog1.InitialDirectory = folderBrowserDialog1.SelectedPath;
            openFileDialog1.FileName = null;
        }

        // Display the openFile dialog.
        DialogResult result = openFileDialog1.ShowDialog();

        // OK button was pressed.
        if (result == DialogResult.OK)
        {
            openFileName = openFileDialog1.FileName;
            try
            {
                // Output the requested file in richTextBox1.
                Stream s = openFileDialog1.OpenFile();
                richTextBox1.LoadFile(s, RichTextBoxStreamType.RichText);
                s.Close();

                fileOpened = true;
            }
            catch (Exception exp)
            {
                MessageBox.Show("An error occurred while attempting to load the file. The error is:"
                                + System.Environment.NewLine + exp.ToString() + System.Environment.NewLine);
                fileOpened = false;
            }
            Invalidate();

            closeMenuItem.Enabled = fileOpened;
        }

        // Cancel button was pressed.
        else if (result == DialogResult.Cancel)
        {
            return;
        }
    }

    // Close the current file.
    private void closeMenuItem_Click(object sender, EventArgs e)
    {
        richTextBox1.Text = "";
        fileOpened = false;

        closeMenuItem.Enabled = false;
    }

    // Bring up a dialog to choose a folder path in which to open or save a file.
    private void folderMenuItem_Click(object sender, EventArgs e)
    {
        // Show the FolderBrowserDialog.
        DialogResult result = folderBrowserDialog1.ShowDialog();
        if (result == DialogResult.OK)
        {
            folderName = folderBrowserDialog1.SelectedPath;
            if (!fileOpened)
            {
                // No file is opened, bring up openFileDialog in selected path.
                openFileDialog1.InitialDirectory = folderName;
                openFileDialog1.FileName = null;
                openMenuItem.PerformClick();
            }
        }
    }
}

' The following example displays an application that provides the ability to 
' open rich text files (rtf) into the RichTextBox. The example demonstrates 
' using the FolderBrowserDialog to set the default directory for opening files.
' The OpenFileDialog class is used to open the file.
Imports System.Drawing
Imports System.Windows.Forms
Imports System.IO

Public Class FolderBrowserDialogExampleForm 
    Inherits Form
    
    Private folderBrowserDialog1 As FolderBrowserDialog
    Private openFileDialog1 As OpenFileDialog 
    
    Private richTextBox1 As RichTextBox

    Private mainMenu1 As MainMenu
    Private fileMenuItem As MenuItem
    Private WithEvents folderMenuItem As MenuItem, _
                       closeMenuItem As MenuItem, _
                       openMenuItem As MenuItem
    
    Private openFileName As String, folderName As String

    Private fileOpened As Boolean = False

    Public Sub New()
        Me.mainMenu1 = New System.Windows.Forms.MainMenu() 
        Me.fileMenuItem = New System.Windows.Forms.MenuItem() 
        Me.openMenuItem = New System.Windows.Forms.MenuItem() 
        Me.folderMenuItem = New System.Windows.Forms.MenuItem() 
        Me.closeMenuItem = New System.Windows.Forms.MenuItem() 

        Me.openFileDialog1 = New System.Windows.Forms.OpenFileDialog() 
        Me.folderBrowserDialog1 = New System.Windows.Forms.FolderBrowserDialog() 
        Me.richTextBox1 = New System.Windows.Forms.RichTextBox() 

        Me.mainMenu1.MenuItems.Add(Me.fileMenuItem) 
        Me.fileMenuItem.MenuItems.AddRange( _
                    New System.Windows.Forms.MenuItem() {Me.openMenuItem, _
                                                         Me.closeMenuItem, _
                                                         Me.folderMenuItem}) 
        Me.fileMenuItem.Text = "File" 

        Me.openMenuItem.Text = "Open..." 

        Me.folderMenuItem.Text = "Select Directory..." 

        Me.closeMenuItem.Text = "Close" 
        Me.closeMenuItem.Enabled = False 

        Me.openFileDialog1.DefaultExt = "rtf" 
        Me.openFileDialog1.Filter = "rtf files (*.rtf)|*.rtf" 

        ' Set the Help text description for the FolderBrowserDialog.
        Me.folderBrowserDialog1.Description = _
            "Select the directory that you want to use As the default." 

        ' Do not allow the user to create New files via the FolderBrowserDialog.
        Me.folderBrowserDialog1.ShowNewFolderButton = False 

        ' Default to the My Documents folder.
        Me.folderBrowserDialog1.RootFolder = Environment.SpecialFolder.Personal 

        Me.richTextBox1.AcceptsTab = True 
        Me.richTextBox1.Location = New System.Drawing.Point(8, 8) 
        Me.richTextBox1.Size = New System.Drawing.Size(280, 344) 
        Me.richTextBox1.Anchor = AnchorStyles.Top Or AnchorStyles.Left Or _
                                 AnchorStyles.Bottom Or AnchorStyles.Right 

        Me.ClientSize = New System.Drawing.Size(296, 360) 
        Me.Controls.Add(Me.richTextBox1) 
        Me.Menu = Me.mainMenu1 
        Me.Text = "RTF Document Browser" 
    End Sub
    
    <STAThread()> _
    Shared Sub Main()
        Application.Run(New FolderBrowserDialogExampleForm())
    End Sub

    ' Bring up a dialog to open a file.
    Private Sub openMenuItem_Click(sender As object, e As System.EventArgs) _
        Handles openMenuItem.Click
        ' If a file is not opened, then set the initial directory to the
        ' FolderBrowserDialog.SelectedPath value.
        If (not fileOpened) Then
            openFileDialog1.InitialDirectory = folderBrowserDialog1.SelectedPath 
            openFileDialog1.FileName = nothing 
        End If

        ' Display the openFile dialog.
        Dim result As DialogResult = openFileDialog1.ShowDialog() 

        ' OK button was pressed.
        If (result = DialogResult.OK) Then
            openFileName = openFileDialog1.FileName 
            Try
                ' Output the requested file in richTextBox1.
                Dim s As Stream = openFileDialog1.OpenFile() 
                richTextBox1.LoadFile(s, RichTextBoxStreamType.RichText) 
                s.Close()     
            
                fileOpened = True 

            Catch exp As Exception
                MessageBox.Show("An error occurred while attempting to load the file. The error is:" _
                                + System.Environment.NewLine + exp.ToString() + System.Environment.NewLine) 
                fileOpened = False 
            End Try
            Invalidate() 

            closeMenuItem.Enabled = fileOpened 

        ' Cancel button was pressed.
        ElseIf (result = DialogResult.Cancel) Then
            return 
        End If
    End Sub

    ' Close the current file.
    Private Sub closeMenuItem_Click(sender As object, e As System.EventArgs) _
        Handles closeMenuItem.Click
        richTextBox1.Text = "" 
        fileOpened = False 

        closeMenuItem.Enabled = False 
    End Sub

    ' Bring up a dialog to chose a folder path in which to open or save a file.
    Private Sub folderMenuItem_Click(sender As object, e As System.EventArgs) _
        Handles folderMenuItem.Click
        ' Show the FolderBrowserDialog.
        Dim result As DialogResult = folderBrowserDialog1.ShowDialog() 

        If ( result = DialogResult.OK ) Then
            folderName = folderBrowserDialog1.SelectedPath 
            If (not fileOpened) Then
                ' No file is opened, bring up openFileDialog in selected path.
                openFileDialog1.InitialDirectory = folderName 
                openFileDialog1.FileName = nothing
                openMenuItem.PerformClick() 
            End If
        End If
    End Sub

End Class

Remarks

The parameterless constructor initializes properties to their default values.

When a new FolderBrowserDialog is created, the RootFolder property is set to Environment.SpecialFolder.Desktop, the Description property is set to an empty string (""), the SelectedPath property is set to an empty string, and the ShowNewFolderButton property is set to true.

Typically, after creating a new FolderBrowserDialog, you set the RootFolder to the location from which to start browsing. Optionally, you can set the SelectedPath to the path of a subfolder of RootFolder that will initially be selected. You can also optionally set the Description property to provide additional instructions to the user. Finally, call the ShowDialog method to display the dialog box to the user. When the dialog box is closed and the dialog result from ShowDialog is DialogResult.OK, the SelectedPath will be a string containing the path to the selected folder.

FolderBrowserDialog is a modal dialog box; therefore, when shown, it blocks the rest of the application until the user has chosen a folder. When a dialog box is displayed modally, no input (keyboard or mouse click) can occur except to objects on the dialog box. The program must hide or close the dialog box (usually in response to some user action) before input to the calling program can occur.

Applies to

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FolderBrowserDialog Constructor

Definition

Examples

Remarks

Applies to

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