protected void Page_Load(object sender, EventArgs e)
    {
        Label1.Text = System.DateTime.Now.ToShortDateString();
        OracleDataAdapter adapter = new OracleDataAdapter();
        DataSet ds = new DataSet();
        //int i = 0;
        string sql = null;
        string connetionString = ("Data Source=TEST;User ID=TEST; Password =TEST ");
        sql = "select * from emp";
        OracleConnection connection = new OracleConnection(connetionString);
        connection.Open();
        OracleCommand command = new OracleCommand(sql, connection);
        adapter.SelectCommand = command;
        adapter.Fill(ds);
        adapter.Dispose();
        command.Dispose();
        connection.Close();
        grdUserList.DataSource = ds.Tables[0];
        grdUserList.DataBind();
    }
    protected void Print(object sender, EventArgs e)
    {
        grdUserList.UseAccessibleHeader = true;
        grdUserList.HeaderRow.TableSection = TableRowSection.TableHeader;
        grdUserList.FooterRow.TableSection = TableRowSection.TableFooter;
        grdUserList.Attributes["style"] = "border-collapse:separate";
        foreach (GridViewRow row in grdUserList.Rows)
        {
            if (row.RowIndex % 10 == 0 && row.RowIndex != 0)
            {
                row.Attributes["style"] = "page-break-after:always;";
            }
        }
        StringWriter sw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(sw);
        grdUserList.RenderControl(hw);
        string gridHTML = sw.ToString().Replace("\"", "'").Replace(System.Environment.NewLine, "");
        StringBuilder sb = new StringBuilder();
        sb.Append("<script type = 'text/javascript'>");
        sb.Append("window.onload = new function(){");
        sb.Append("var printWin = window.open('', '', 'left=0");
        sb.Append(",top=0,width=1000,height=600,status=0');");
        sb.Append("printWin.document.write(\"");
        string style = "<style type = 'text/css'>thead {display:table-header-group;} tfoot{display:table-footer-group;}</style>";
        sb.Append(style + gridHTML);
        sb.Append("\");");
        sb.Append("printWin.document.close();");
        sb.Append("printWin.focus();");
        sb.Append("printWin.print();");
        sb.Append("printWin.close();");
        sb.Append("};");
        sb.Append("</script>");
        ClientScript.RegisterStartupScript(this.GetType(), "GridPrint", sb.ToString());
        grdUserList.DataBind();
    }
    int tempcounter = 0;
    protected void grdUserList_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            tempcounter = tempcounter + 1;
            if (tempcounter == 10)
            {
                e.Row.Attributes.Add("style", "page-break-after: always;");
                tempcounter = 0;
            }
        }
    }
    public override void VerifyRenderingInServerForm(Control control)
    {
        /*Verifies that the control is rendered */
    }
}
HI 
I AM GETTING JavaScript runtime error: Unable to get property 'document' of undefined or null reference ERROR
what i am trying to do is print the gridview data 
so can any one help me