private void btnRemoveFromList_Click(object sender, EventArgs e)
        {
            if (lst_Users.SelectedItems.Count == 0 || List_User_Application == null)
            {
                return;
            }

            User_cu selecteduser = (User_cu)lst_Users.SelectedItem;

            if (selecteduser == null)
            {
                return;
            }
            if (List_SelectedUserToBedAdded.Exists(
                    item => Convert.ToInt32(item.ID).Equals(Convert.ToInt32(selecteduser.ID))))
            {
                List_SelectedUserToBedAdded.Remove(selecteduser);
            }

            CommonViewsActions.FillListBoxControl(lst_Users, List_SelectedUserToBedAdded, "FullName", "Person_CU_ID");
            lst_Users.Refresh();

            User_Application_cu userBridge =
                List_User_Application.Find(
                    item => Convert.ToInt32(item.User_CU_ID).Equals(Convert.ToInt32(selecteduser.ID)));

            if (userBridge == null)
            {
                return;
            }
            List_User_Application.Remove(userBridge);
        }