Printing Datagrid table with many column headers across multiple pages in asp.net

First I want to say that you are not printing the datagrid but the html generated by this. Hence, you need to do something on the client side. Since you wrote, you need to break the table and then print. I am attaching a html page from where you can copy the code and modify it to work with your datagrid generated html, you will need to at least change the datagrid id.

Here follows the code

[since you didn't provide the generated html, I made a similar table]

<table id="previousOrderExports" class="chromeTheme">
    <tr>
        <td class="bold">Export ID</td>
        <td class="bold">Request Type</td>
        <td class="bold">Timeframe</td>
        <td class="bold">Search Filter</td>
        <td class="bold">Search Term</td>
        <td class="bold">Requested on</td>
        <td class="bold">Processed on</td>
        <td class="bold">Export Status</td>
        <td class="bold">Download</td>
    </tr>
    <tr>
        <td>143306</td>
        <td>manual</td>
        <td>11/8/14 - 12/8/14</td>
        <td>Timespan</td>
        <td></td>
        <td>12/08/14 03:37:00 AM PST</td>
        <td>12/08/14 03:37:08 AM PST</td>
        <td>Done</td>
        <td><a href="fghhsd.dsfd/sfre/143306">Download</a></td>
    </tr>
    <tr>
        <td>142873</td>
        <td>auto</td>
        <td>12/7/14 - 12/8/14</td>
        <td>Timespan</td>
        <td></td>
        <td>12/08/14 01:01:10 AM PST</td>
        <td>12/08/14 01:03:00 AM PST</td>
        <td>Done</td>
        <td><a href="fghhsd.dsfd/sfre/142873">Download</a></td>
    </tr>
    <tr>
        <td>142766</td>
        <td>auto</td>
        <td>12/7/14 - 12/8/14</td>
        <td>Timespan</td>
        <td></td>
        <td>12/07/14 11:01:03 PM PST</td>
        <td>12/07/14 11:02:04 PM PST</td>
        <td>Done</td>
        <td><a href="fghhsd.dsfd/sfre/142766">Download</a></td>
    </tr>
    <tr>
        <td>142752</td>
        <td>auto</td>
        <td>12/7/14 - 12/8/14</td>
        <td>Timespan</td>
        <td></td>
        <td>12/07/14 10:01:03 PM PST</td>
        <td>12/07/14 10:02:05 PM PST</td>
        <td>Done</td>
        <td><a href="fghhsd.dsfd/sfre/142752">Download</a></td>
    </tr>
    <tr>
        <td>142738</td>
        <td>auto</td>
        <td>12/7/14 - 12/8/14</td>
        <td>Timespan</td>
        <td></td>
        <td>12/07/14 09:01:03 PM PST</td>
        <td>12/07/14 09:02:07 PM PST</td>
        <td>Done</td>
        <td><a href="fghhsd.dsfd/sfre/142738">Download</a></td>
    </tr>
    <tr>
        <td>142723</td>
        <td>auto</td>
        <td>12/7/14 - 12/8/14</td>
        <td>Timespan</td>
        <td></td>
        <td>12/07/14 08:01:02 PM PST</td>
        <td>12/07/14 08:02:04 PM PST</td>
        <td>Done</td>
        <td><a href="fghhsd.dsfd/sfre/142723">Download</a></td>
    </tr>
    <tr>
        <td>142709</td>
        <td>auto</td>
        <td>12/7/14 - 12/8/14</td>
        <td>Timespan</td>
        <td></td>
        <td>12/07/14 07:01:03 PM PST</td>
        <td>12/07/14 07:02:04 PM PST</td>
        <td>Done</td>
        <td><a href="fghhsd.dsfd/sfre/142709">Download</a></td>
    </tr>
</table>
<input id="Button1" type="button" value="Print" onclick="print_breakup_table()" />
 <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js" language="javascript" type="text/javascript"></script>
<script language="javascript" type="text/javascript">
    function print_breakup_table()
    {
        var tableid = "previousOrderExports"; //id of table in this case cliend side id of your datagrid
        var fixedcols = 2;// no. of columns 0 index based that will be repeated on every page
        var eachpagecols = 3; // no. of columns that will get printed on each page
        var colCount = 0;
        $('#' + tableid + ' tr:nth-child(1) td').each(function () {
            if ($(this).attr('colspan')) {
                colCount += +$(this).attr('colspan');
            } else {
                colCount++;
            }
        });
        colCount--; //get 0 based columncount
        var col_left_after_fixed_col = colCount - fixedcols;
        var pagerequired = col_left_after_fixed_col / eachpagecols;
        if ((col_left_after_fixed_col % eachpagecols)>0) {
            pagerequired++;
        }
        for (var i = 0; i < pagerequired; i++) {
            var html = "<table>";
            var startcols = fixedcols + (i * eachpagecols);
            var endcols = startcols + eachpagecols;
            //add fixed cols
            $('#' + tableid + ' tr').each(function () {
                html += "<tr>";
                $(this).children('td').each(function (index, object) {
                    if (index <= fixedcols) {
                        html += "<td>" + $(this).html() + "</td>";
                    } else {
                        if (index <= endcols && index >= startcols) {
                            html += "<td>" + $(this).html() + "</td>";
                        }
                    }
                });
                html += "</tr>";
            });



            html += "</table>";
            myWindow = window.open('', '', 'width=800,height=600');
            myWindow.document.write(html);


            myWindow.document.close();


            myWindow.focus();
            myWindow.print();
        }

    }
</script>