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.NET Framework Class Library
FileDialog..::.FilterIndex Property

Gets or sets the index of the filter currently selected in the file dialog box.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
Syntax
Public Property FilterIndex As Integer
public int FilterIndex { get; set; }
public:
property int FilterIndex {
	int get ();
	void set (int value);
}
member FilterIndex : int with get, set

Property Value

Type: System..::.Int32
A value containing the index of the filter currently selected in the file dialog box. The default value is 1.
Remarks

Use the FilterIndex property to set which filtering option is shown first to the user. You can also use the value of FilterIndex after showing the file dialog to perform special file operations depending upon the filter chosen.

NoteNote

The index value of the first filter entry is 1.

Examples

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 Filter and FilterIndex properties to provide a list of filters for the user. The example requires a form with a Button placed on it and the System.IO namespace added to it.


    Private Sub button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim myStream As Stream = Nothing
        Dim openFileDialog1 As New OpenFileDialog()

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

        If openFileDialog1.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
            Try
                myStream = openFileDialog1.OpenFile()
                If (myStream IsNot Nothing) Then
                    ' Insert code to read the stream here.
                End If
            Catch Ex As Exception
                MessageBox.Show("Cannot read file from disk. Original error: " & Ex.Message)
            Finally
                ' Check this again, since we need to make sure we didn't throw an exception on open.
                If (myStream IsNot Nothing) Then
                    myStream.Close()
                End If
            End Try
        End If
    End Sub



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)
    {
        try
        {
            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);
        }
    }
}
    


private:
   void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      Stream^ myStream;
      OpenFileDialog^ openFileDialog1 = gcnew OpenFileDialog;

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

      if ( openFileDialog1->ShowDialog() == System::Windows::Forms::DialogResult::OK )
      {
         if ( (myStream = openFileDialog1->OpenFile()) != nullptr )
         {
            // Insert code to read the stream here.
            myStream->Close();
         }
      }
   }

Version Information

.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
Platforms

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.