title: ComboBox selection cleared in a tab control
body: <p>I am doing c# winform development.</p>
  
  <p>I have a tabcontrol that consists several tabpages. Some of the tabpages are filled with usercontrol fully, some are just filled with combboxes/textboxes as such. </p>
  
  <p>I set datasource for comboboxes and it loaded ok. But, when I pass the entire tabcontrol instance as a parameter to another form, in the new form, the combo box selections are cleared and set to first item selected.</p>
  
  <p>Strangely enough, for comboboxes that was put in a usercontrol, the selections were not clear and shown correctly in the new form. Only those were put directly in tab page do not work.</p>
  
  <p>Any suggestions or help will be appreciated. </p>