private void btnLoguot_Click(object sender, EventArgs e)
{
frm_DangNhap dn = new frm_DangNhap();
this.Close();
dn.Show();
}
private void btnXacNhan_Click(object sender, EventArgs e)
{
QL_NguoiDung.SaveConfig(cbbServerName.Text, txtUser.Text, txtPassword.Text, cbbDataBase.Text);
frm_DangNhap dn = new frm_DangNhap();
dn.Show();
this.Close();
}