[c#]
//FlyGrid initialization
private void InitGrid(FlyGrid flyGrid)
{
  //....
  flyGrid.Columns.Items[0].Caption = \"Application Folder\";
  //setup editor style
  flyGrid.Columns.Items[0].EditorStyle = EditorStyle.Dialog;
  //connect to the DialogButtonClick event handler
  flyGrid.DialogButtonClick += new NineRays.Windows.Forms.FlyGrid.DialogButtonClickHandler(flyGrid_DialogButtonClick);
}

//DialogButtonClick event handler
private void flyGrid_DialogButtonClick(object sender, FlyGridViewPort port, Column col, NodeBase node)
{
  FolderBrowserDialog fbd = new FolderBrowserDialog();
  fbd.Description = \"Choose folder for \" + col.Caption;
  fbd.ShowNewFolderButton = true;
  string value = col.GetTextValue(node);
  if (value != null && value != string.Empty)
    fbd.SelectedPath = value;
  if (fbd.ShowDialog(this) == DialogResult.OK)
  {
    col.SetValue(node, fbd.SelectedPath);
  }
}

[VB.Net]
'flyGrid initialization
Private Sub InitFlyGrid(ByVal flyGrid As FlyGrid)
  '....
  flyGrid.Columns.Items(0).Caption = \"Application Folder\"
  'setup editor style
  flyGrid.Columns.Items(0).EditorStyle = EditorStyle.Dialog
  'connect to the DialogButtonClick event handler
  AddHandler flyGrid.DialogButtonClick, AddressOf flyGrid_DialogButtonClick
End Sub

'DialogButtonClick event handler
Private Sub flyGrid_DialogButtonClick(ByVal sender As Object, ByVal port As FlyGridViewPort, ByVal col As Column, ByVal node As NodeBase)
  Dim fbd As New FolderBrowserDialog
  fbd.Description = \"Choose folder for \" + col.Caption
  fbd.ShowNewFolderButton = True
  Dim value As String = col.GetTextValue(node)
  If (Not value Is Nothing And value  String.Empty) Then
    fbd.SelectedPath = value
  End If
  If (fbd.ShowDialog(Me) = DialogResult.OK) Then
    col.SetValue(node, fbd.SelectedPath)
  End If
End Sub