gridview 中SelectedIndexChanged 事件获得该行主键

protected void gvSuppliers_SelectedIndexChanged(object sender, EventArgs e)
        {
            lblCompany.Visible = true;
            lblCompanyName.Text = gvSuppliers.SelectedDataKey["CompanyName"].ToString();
            hfZeroDefect.Value = gvSuppliers.SelectedDataKey["SnID"].ToString() + ";" + gvSuppliers.SelectedDataKey["CompanyName"].ToString() + ";"
                + ddlYear.SelectedValue + ";" + ddlMonth.SelectedValue;

。。

}