This documentation is archived and is not being maintained.

FileDialog Class

Displays a dialog box from which the user can select a file.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public abstract class FileDialog : CommonDialog

The FileDialog type exposes the following members.

Public propertyAddExtensionGets or sets a value indicating whether the dialog box automatically adds an extension to a file name if the user omits the extension.
Public propertyAutoUpgradeEnabledGets or sets a value indicating whether this FileDialog instance should automatically upgrade appearance and behavior when running on Windows Vista.
Protected propertyCanRaiseEventsGets a value indicating whether the component can raise an event. (Inherited from Component.)
Public propertyCheckFileExistsGets or sets a value indicating whether the dialog box displays a warning if the user specifies a file name that does not exist.
Public propertyCheckPathExistsGets or sets a value indicating whether the dialog box displays a warning if the user specifies a path that does not exist.
Public propertyContainerGets the IContainer that contains the Component. (Inherited from Component.)
Public propertyCustomPlacesGets the custom places collection for this FileDialog instance.
Public propertyDefaultExtGets or sets the default file name extension.
Public propertyDereferenceLinksGets or sets a value indicating whether the dialog box returns the location of the file referenced by the shortcut or whether it returns the location of the shortcut (.lnk).
Protected propertyDesignModeGets a value that indicates whether the Component is currently in design mode. (Inherited from Component.)
Protected propertyEventsGets the list of event handlers that are attached to this Component. (Inherited from Component.)
Public propertyFileNameGets or sets a string containing the file name selected in the file dialog box.
Public propertyFileNamesGets the file names of all selected files in the dialog box.
Public propertyFilterGets or sets the current file name filter string, which determines the choices that appear in the "Save as file type" or "Files of type" box in the dialog box.
Public propertyFilterIndexGets or sets the index of the filter currently selected in the file dialog box.
Public propertyInitialDirectoryGets or sets the initial directory displayed by the file dialog box.
Protected propertyInstanceInfrastructure. Gets the Win32 instance handle for the application.
Protected propertyOptionsInfrastructure. Gets values to initialize the FileDialog.
Public propertyRestoreDirectoryGets or sets a value indicating whether the dialog box restores the current directory before closing.
Public propertyShowHelpGets or sets a value indicating whether the Help button is displayed in the file dialog box.
Public propertySiteGets or sets the ISite of the Component. (Inherited from Component.)
Public propertySupportMultiDottedExtensionsGets or sets whether the dialog box supports displaying and saving files that have multiple file name extensions.
Public propertyTagGets or sets an object that contains data about the control. (Inherited from CommonDialog.)
Public propertyTitleGets or sets the file dialog box title.
Public propertyValidateNamesGets or sets a value indicating whether the dialog box accepts only valid Win32 file names.

Public methodCreateObjRefCreates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object. (Inherited from MarshalByRefObject.)
Public methodDispose()Releases all resources used by the Component. (Inherited from Component.)
Protected methodDispose(Boolean)Releases the unmanaged resources used by the Component and optionally releases the managed resources. (Inherited from Component.)
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodFinalizeReleases unmanaged resources and performs other cleanup operations before the Component is reclaimed by garbage collection. (Inherited from Component.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetLifetimeServiceRetrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject.)
Protected methodGetServiceReturns an object that represents a service provided by the Component or by its Container. (Inherited from Component.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodHookProcDefines the common dialog box hook procedure that is overridden to add specific functionality to the file dialog box. (Overrides CommonDialog.HookProc(IntPtr, Int32, IntPtr, IntPtr).)
Public methodInitializeLifetimeServiceObtains a lifetime service object to control the lifetime policy for this instance. (Inherited from MarshalByRefObject.)
Protected methodMemberwiseClone()Creates a shallow copy of the current Object. (Inherited from Object.)
Protected methodMemberwiseClone(Boolean)Creates a shallow copy of the current MarshalByRefObject object. (Inherited from MarshalByRefObject.)
Protected methodOnFileOkRaises the FileOk event.
Protected methodOnHelpRequestRaises the HelpRequest event. (Inherited from CommonDialog.)
Protected methodOwnerWndProcDefines the owner window procedure that is overridden to add specific functionality to a common dialog box. (Inherited from CommonDialog.)
Public methodResetResets all properties to their default values. (Overrides CommonDialog.Reset().)
Protected methodRunDialogInfrastructure. Specifies a common dialog box. (Overrides CommonDialog.RunDialog(IntPtr).)
Public methodShowDialog()Runs a common dialog box with a default owner. (Inherited from CommonDialog.)
Public methodShowDialog(IWin32Window)Runs a common dialog box with the specified owner. (Inherited from CommonDialog.)
Public methodToStringInfrastructure. Provides a string version of this object. (Overrides Component.ToString().)

Public eventDisposedOccurs when the component is disposed by a call to the Dispose method. (Inherited from Component.)
Public eventFileOkOccurs when the user clicks on the Open or Save button on a file dialog box.
Public eventHelpRequestOccurs when the user clicks the Help button on a common dialog box. (Inherited from CommonDialog.)

Protected fieldStatic memberEventFileOkInfrastructure. Owns the FileOk event.

FileDialog is an abstract class that contains common behavior for the OpenFileDialog and SaveFileDialog classes. It is not intended to be used directly but contains common behavior for those two classes. You cannot create an instance of FileDialog. Although the class is declared public, you cannot inherit from it, as it contains internal abstract methods. To create a dialog box to select or save a file, use OpenFileDialog or SaveFileDialog.

FileDialog is a modal dialog box; therefore, when shown, it blocks the rest of the application until the user has chosen a file. 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.

Caution noteCaution

When you use classes derived from FileDialog, such as OpenFileDialog and SaveFileDialog, avoid using string literals containing absolute paths. Instead, dynamically obtain the path using one or more of the techniques described in the following table.

If you want to enable users to select a folder instead of a file, use the FolderBrowserDialog.

Depending upon the type of application, how data associated with the application is stored, and the reason for accessing the file system, there are many possible ways in which you can create a directory path. The following table shows the techniques for creating paths dynamically.

Path or program category

Class and members to use

Standard Windows paths, such as Program Files, MyDocuments, the Desktop and so on

The System.Environment class is the most complete source for these, either through its static methods, such as SystemDirectory, or through the GetFolderPath method, using one of the Environment.SpecialFolder enumerated values.

Paths related to the current application

The Application class has static members to obtain certain paths, such as StartupPath, ExecutablePath, LocalUserAppDataPath, and CommonAppDataPath.

The GetTempPath method of the System.IO.Path returns the path of the temporary folder.

The GetCurrentDirectory method of the System.IO.Directory class returns the application's current executing directory.

The RootDirectory property of the DriveInfo class represents the specified drive's root directory.

Paths stored as application settings

Access the corresponding applications settings property of the wrapper class derived from ApplicationSettingsBase. For more information, see Application Settings for Windows Forms.

Registry storage

Some applications store directory information in the registry. The Application class has the CommonAppDataPath and LocalUserAppDataPath properties that resolve to a RegistryKey value.

ClickOnce applications

For ClickOnce applications, use Application class members such as UserAppDataPath, which will return a pointer to the ClickOnce data directory. For more information, see Accessing Local and Remote Data in ClickOnce Applications.

International applications

For international applications, retrieve the relative path portion from a string resource in your application by using the System.Resources.ResourceReader class. For more information about globalization and localization, see the topic Encoding and Localization.

Notice that a full path may be built up using one or more of the described techniques. For example, the GetFolderPath method might be used to obtain the path to the MyDocuments folder, then an application setting may be used to add a relative subdirectory portion.

The System.IO.Path class contains static members to assist in manipulating absolute and relative path strings, whereas the System.IO.File and System.IO.Directory classes have static members that actually manipulate files and directories, respectively.

Important noteImportant

If the user of your application changes the folder in the FileDialog, then the current working directory for your application is set to the location specified in the FileDialog. To prevent this, set the RestoreDirectory property to true.

The following code example uses the OpenFileDialog implementation of FileDialog and illustrates creating, setting of properties, and showing the dialog box. The example uses the ShowDialog method to display the dialog box and return the DialogResult. The example requires a form with a Button placed on it and the System.IO namespace added to it.

private void button1_Click(object sender, System.EventArgs e)
    Stream myStream = null;
    OpenFileDialog openFileDialog1 = new OpenFileDialog();

    openFileDialog1.InitialDirectory = "c:\\" ;
    openFileDialog1.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*" ;
    openFileDialog1.FilterIndex = 2 ;
    openFileDialog1.RestoreDirectory = true ;

    if(openFileDialog1.ShowDialog() == DialogResult.OK)
            if ((myStream = openFileDialog1.OpenFile()) != null)
                using (myStream)
                    // Insert code to read the stream here.
        catch (Exception ex)
            MessageBox.Show("Error: Could not read file from disk. Original 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 SP1

Windows 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.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.