public void setCmbSemester() { systemManager objsystemManager = new systemManager(); cmbSemster.DataSource = objsystemManager.GetSemeDatatoStuSemAllocation(); cmbSemster.ValueMember = "SemesterID"; cmbSemster.DisplayMember = "SemesterCode"; //because of this department combo's display inedex will shown as a blank index cmbSemster.SelectedIndex = -1; }