You could achieve your goal by using the demo application I have sent you. You just need to modify it a bit. You need to add one additional RadComboBox control and to modify the respective methods, namely:
_combo.DataTextField = DataTextField;
_combo.DataValueField = DataValueField;
_combo.DataSource = DataSource;
_combo2.DataTextField = DataTextField;
_combo2.DataValueField = DataValueField;
_combo2.DataSource = DataSource;
and so on.
Give this approach a try and check whether you get the expected behavior.
the Telerik team
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