private void load_data_to_combobox_khoan_tien()
{
US_CM_DM_TU_DIEN v_us = new US_CM_DM_TU_DIEN();
DS_CM_DM_TU_DIEN v_ds = new DS_CM_DM_TU_DIEN();
v_us.FillDatasetByIdLoaiTuDien(v_ds, 19);
m_cmb_khoan_tien.DataSource = v_ds.Tables[0];
m_cmb_khoan_tien.DisplayMember = "TEN";
m_cmb_khoan_tien.ValueMember = "ID";
}