FolderBrowserDialog 类
提示用户选择文件夹。无法继承此类。
**命名空间:**System.Windows.Forms
**程序集:**System.Windows.Forms(在 system.windows.forms.dll 中)
语法
声明
Public NotInheritable Class FolderBrowserDialog
Inherits CommonDialog
用法
Dim instance As FolderBrowserDialog
public sealed class FolderBrowserDialog : CommonDialog
public ref class FolderBrowserDialog sealed : public CommonDialog
public final class FolderBrowserDialog extends CommonDialog
public final class FolderBrowserDialog extends CommonDialog
备注
此类提供一种方法,它提示用户浏览、创建并最终选择一个文件夹。如果只允许用户选择文件夹而非文件,则可使用此类。文件夹的浏览通过树控件完成。只能选择文件系统中的文件夹;不能选择虚拟文件夹。
通常在创建新 FolderBrowserDialog 后,将 RootFolder 设置为开始浏览的位置。或者,可将 SelectedPath 设置为最初选定的 RootFolder 子文件夹的绝对路径。也可以选择设置 Description 属性为用户提供附加说明。最后,调用 ShowDialog 方法将对话框显示给用户。如果该对话框关闭并且 ShowDialog 显示的对话框为 DialogResult.OK,SelectedPath 则是一个包含选定文件夹路径的字符串。
如果用户可通过“新建文件夹”按钮创建新文件夹,则可对控件使用 ShowNewFolderButton 属性。
FolderBrowserDialog 是有模式对话框,因此,在显示时,它会阻止应用程序剩余部分的运行,直到用户选定了文件夹。当对话框有模式显示时,不能进行任何输入(通过键盘或鼠标单击),对对话框上的对象的输入除外。在对调用程序进行输入之前,程序必须隐藏或关闭对话框(通常是响应某一用户操作)。
示例
下面的代码示例创建一个应用程序,用户使用该应用程序可以打开 RichTextBox 控件中的多格式文本 (.rtf) 文件。
' 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
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
// 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 MainMenu mainMenu1;
private MenuItem fileMenuItem, openMenuItem;
private MenuItem folderMenuItem, closeMenuItem;
private string openFileName, folderName;
private bool fileOpened = false;
// The main entry point for the application.
static void Main()
{
Application.Run(new FolderBrowserDialogExampleForm());
}
// Constructor.
public FolderBrowserDialogExampleForm()
{
this.mainMenu1 = new System.Windows.Forms.MainMenu();
this.fileMenuItem = new System.Windows.Forms.MenuItem();
this.openMenuItem = new System.Windows.Forms.MenuItem();
this.folderMenuItem = new System.Windows.Forms.MenuItem();
this.closeMenuItem = new System.Windows.Forms.MenuItem();
this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
this.folderBrowserDialog1 = new System.Windows.Forms.FolderBrowserDialog();
this.richTextBox1 = new System.Windows.Forms.RichTextBox();
this.mainMenu1.MenuItems.Add(this.fileMenuItem);
this.fileMenuItem.MenuItems.AddRange(
new System.Windows.Forms.MenuItem[] {this.openMenuItem,
this.closeMenuItem,
this.folderMenuItem});
this.fileMenuItem.Text = "File";
this.openMenuItem.Text = "Open...";
this.openMenuItem.Click += new System.EventHandler(this.openMenuItem_Click);
this.folderMenuItem.Text = "Select Directory...";
this.folderMenuItem.Click += new System.EventHandler(this.folderMenuItem_Click);
this.closeMenuItem.Text = "Close";
this.closeMenuItem.Click += new System.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, 8);
this.richTextBox1.Size = new System.Drawing.Size(280, 344);
this.richTextBox1.Anchor = AnchorStyles.Top | AnchorStyles.Left |
AnchorStyles.Bottom | AnchorStyles.Right;
this.ClientSize = new System.Drawing.Size(296, 360);
this.Controls.Add(this.richTextBox1);
this.Menu = this.mainMenu1;
this.Text = "RTF Document Browser";
}
// Bring up a dialog to open a file.
private 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 = 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, System.EventArgs e)
{
richTextBox1.Text = "";
fileOpened = false;
closeMenuItem.Enabled = false;
}
// Bring up a dialog to chose a folder path in which to open or save a file.
private void folderMenuItem_Click(object sender, System.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 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.
import System.*;
import System.Drawing.*;
import System.Windows.Forms.*;
import System.IO.*;
public class FolderBrowserDialogExampleForm extends System.Windows.Forms.Form
{
private FolderBrowserDialog folderBrowserDialog1;
private OpenFileDialog openFileDialog1;
private RichTextBox richTextBox1;
private MainMenu mainMenu1;
private MenuItem fileMenuItem, openMenuItem;
private MenuItem folderMenuItem, closeMenuItem;
private String openFileName, folderName;
private boolean fileOpened = false;
// The main entry point for the application.
public static void main(String[] args)
{
Application.Run(new FolderBrowserDialogExampleForm());
} //main
// Constructor.
public FolderBrowserDialogExampleForm()
{
this.mainMenu1 = new System.Windows.Forms.MainMenu();
this.fileMenuItem = new System.Windows.Forms.MenuItem();
this.openMenuItem = new System.Windows.Forms.MenuItem();
this.folderMenuItem = new System.Windows.Forms.MenuItem();
this.closeMenuItem = new System.Windows.Forms.MenuItem();
this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
this.folderBrowserDialog1 =
new System.Windows.Forms.FolderBrowserDialog();
this.richTextBox1 = new System.Windows.Forms.RichTextBox();
this.mainMenu1.get_MenuItems().Add(this.fileMenuItem);
this.fileMenuItem.get_MenuItems().AddRange(
new System.Windows.Forms.MenuItem[] { this.openMenuItem,
this.closeMenuItem, this.folderMenuItem });
this.fileMenuItem.set_Text("File");
this.openMenuItem.set_Text("Open...");
this.openMenuItem.add_Click(new System.EventHandler(
this.openMenuItem_Click));
this.folderMenuItem.set_Text("Select Directory...");
this.folderMenuItem.add_Click(new System.EventHandler(
this.folderMenuItem_Click));
this.closeMenuItem.set_Text("Close");
this.closeMenuItem.add_Click(new System.EventHandler(
this.closeMenuItem_Click));
this.closeMenuItem.set_Enabled(false);
this.openFileDialog1.set_DefaultExt("rtf");
this.openFileDialog1.set_Filter("rtf files (*.rtf)|*.rtf");
// Set the help text description for the FolderBrowserDialog.
this.folderBrowserDialog1.set_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.set_ShowNewFolderButton(false);
// Default to the My Documents folder.
this.folderBrowserDialog1.set_RootFolder(
Environment.SpecialFolder.Personal);
this.richTextBox1.set_AcceptsTab(true);
this.richTextBox1.set_Location(new System.Drawing.Point(8, 8));
this.richTextBox1.set_Size(new System.Drawing.Size(280, 344));
this.richTextBox1.set_Anchor(AnchorStyles.Top | AnchorStyles.Left
| AnchorStyles.Bottom | AnchorStyles.Right);
this.set_ClientSize(new System.Drawing.Size(296, 360));
this.get_Controls().Add(this.richTextBox1);
this.set_Menu(this.mainMenu1);
this.set_Text("RTF Document Browser");
} //FolderBrowserDialogExampleForm
// Bring up a dialog to open a file.
private 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.set_InitialDirectory(
folderBrowserDialog1.get_SelectedPath());
openFileDialog1.set_FileName(null);
}
// Display the openFile dialog.
DialogResult result = openFileDialog1.ShowDialog();
// OK button was pressed.
if (result.Equals(get_DialogResult().OK)) {
openFileName = openFileDialog1.get_FileName();
try {
// Output the requested file in richTextBox1.
Stream s = openFileDialog1.OpenFile();
richTextBox1.LoadFile(s, RichTextBoxStreamType.RichText);
s.Close();
fileOpened = true;
}
catch (System.Exception exp) {
MessageBox.Show("An error occurred while attempting to "
+ "load the file. The error is:"
+ System.Environment.get_NewLine()
+ exp.ToString() + System.Environment.get_NewLine());
fileOpened = false;
}
Invalidate();
closeMenuItem.set_Enabled(fileOpened);
}
// Cancel button was pressed.
else {
if (result.Equals(get_DialogResult().Cancel)) {
return;
}
}
} //openMenuItem_Click
// Close the current file.
private void closeMenuItem_Click(Object sender, System.EventArgs e)
{
richTextBox1.set_Text("");
fileOpened = false;
closeMenuItem.set_Enabled(false);
} //closeMenuItem_Click
// Bring up a dialog to chose a folder path in which to open or save a file.
private void folderMenuItem_Click(Object sender, System.EventArgs e)
{
// Show the FolderBrowserDialog.
DialogResult result = folderBrowserDialog1.ShowDialog();
if (result.Equals(get_DialogResult().OK)) {
folderName = folderBrowserDialog1.get_SelectedPath();
if (!(fileOpened)) {
// No file is opened, bring up openFileDialog in selected path.
openFileDialog1.set_InitialDirectory(folderName);
openFileDialog1.set_FileName(null);
openMenuItem.PerformClick();
}
}
} //folderMenuItem_Click
} //FolderBrowserDialogExampleForm
继承层次结构
System.Object
System.MarshalByRefObject
System.ComponentModel.Component
System.Windows.Forms.CommonDialog
System.Windows.Forms.FolderBrowserDialog
线程安全
此类型的任何公共静态(Visual Basic 中的 Shared)成员都是线程安全的,但不保证所有实例成员都是线程安全的。
平台
Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表,请参见系统要求。
版本信息
.NET Framework
受以下版本支持:2.0、1.1
请参见
参考
FolderBrowserDialog 成员
System.Windows.Forms 命名空间
RootFolder
SelectedPath
ShowDialog