private void Student_Load(object sender, EventArgs e)
{
DataTable dt = c.Select();
metroGrid7.DataSource = dt;
DataTable dtp = p.Select();
metroGrid2.DataSource = dtp;
DataTable dtgn = gn.Select();
metroGrid3.DataSource = dtgn;
DataTable dtsgn = sgn.Select();
metroGrid1.DataSource = dtsgn;
DataTable dtgid = gid.Select();
metroGrid4.DataSource = dtgid;
DataTable dtsgid = sgid.Select();
metroGrid5.DataSource = dtsgid;
}