How to get "PART_CommitButton" Button?

[Zhang]

For using Commands with DataForm, i need references of buttons which with a "PART_" prefix.
Find DataForm.FindName("PART_CommitButton")" returns null. Is there any way?

[Zhang]

I found the way. The code snippet as follows and must be placed at loaded event:
                
        void MainWindow_Loaded(object sender, RoutedEventArgs e)
        {
            var btns = DataForm1.ChildrenOfType<RadButton>();
            var btnCommit = btns.Single(x => x.Name == "PART_CommitButton");
            btnCommit.Command = CommitCommand;     
        }