How to get the selected text from a TextBox cell?

// form()
// Trigger the required event.
gridControl1.CurrentCellStartEditing += gridControl1_CurrentCellStartEditing;
 
void gridControl1_CurrentCellStartEditing(object sender, CancelEventArgs e)
{
    GridCurrentCell cc = this.gridControl1.CurrentCell;
    if (cc.Renderer is GridTextBoxCellRenderer)
    {
       GridTextBoxCellRenderer renderer = cc.Renderer as GridTextBoxCellRenderer;
       renderer.TextBox.MouseUp += TextBox_MouseUp;
    }
}
 
void TextBox_MouseUp(object sender, MouseEventArgs e)
{
    TextBox text = sender as TextBox;
    if (text.SelectionLength > 0)
    {
        MessageBox.Show(text.SelectedText);
    }
}

' form()
' Trigger the required event.
Private gridControl1.CurrentCellStartEditing += AddressOf gridControl1_CurrentCellStartEditing
 
Private Sub gridControl1_CurrentCellStartEditing(ByVal sender As Object, ByVal e As CancelEventArgs)
 Dim cc As GridCurrentCell = Me.gridControl1.CurrentCell
 If TypeOf cc.Renderer Is GridTextBoxCellRenderer Then
    Dim renderer As GridTextBoxCellRenderer = TryCast(cc.Renderer, GridTextBoxCellRenderer)
    AddHandler renderer.TextBox.MouseUp, AddressOf TextBox_MouseUp
 End If
End Sub
 
Private Sub TextBox_MouseUp(ByVal sender As Object, ByVal e As MouseEventArgs)
 Dim text As TextBox = TryCast(sender, TextBox)
 If text.SelectionLength > 0 Then
  MessageBox.Show(text.SelectedText)
 End If
End Sub