Gets 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.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
For each filtering option, the filter string contains a description of the filter, followed by the vertical bar (|) and the filter pattern. The strings for different filtering options are separated by the vertical bar.
The following is an example of a filter string:
Text files (*.txt)|*.txt|All files (*.*)|*.*
You can add several filter patterns to a filter by separating the file types with semicolons, for example:
Image Files(*.BMP;*.JPG;*.GIF)|*.BMP;*.JPG;*.GIF|All files (*.*)|*.*
Use the FilterIndex property to set which filtering option is shown first to the user.
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 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