protected void uiButtonUpdate_Click(object sender, EventArgs e)
 {
     DBLayer db = new DBLayer();
     if (CurrentClass != 0)
     {
         db.UpdateClass(CurrentClass, uiTextBoxEnName.Text, uiTextBoxArName.Text, Convert.ToInt32(uiDropDownListClassType.SelectedValue));
     }
     else
     {
         db.AddClass(uiTextBoxEnName.Text, uiTextBoxArName.Text, Convert.ToInt32(uiDropDownListClassType.SelectedValue));
     }
     uiPanelCurrentClasses.Visible = true;
     uiPanelCurrent.Visible = false;
     ClearFields();
     BindData();
 }