public void DisplayForPresent(ref int m_trang_thai_buoc_1)
{
m_cmd_sua.Enabled = false;
//m_cmd_tai_file_excel_mau.Enabled = false;
m_cmd_chon_file.Enabled = false;
this.CenterToScreen();
this.ShowDialog();
m_trang_thai_buoc_1 = m_trang_thai_buoc_1_sau_hien_thi;
}