First Heading ROW not exported only in PDF format

[Aragorn2004]

Hi, i've a table where heading has two rows. The first row is not exported in PDF file in others format has exported well.

is it a bug or i made a mistake?

HEAD
ID	NAME	DatePers	Level1	Level2	Level3

           <thead>
                    <tr>
                        <th class="col-xs-12" colspan="6">HEAD</th>
                    </tr>
                    <tr>
                        <th class="col-xs-2" data-field="ID">ID</th>
                        <th class="col-xs-4" data-field="NAME">NAME</th>
                        <th class="col-xs-1" data-field="DATAPERS">DatePers</th>
                        <th class="col-xs-1 text-center" data-field="Level1">Level1</th>
                        <th class="col-xs-3" data-field="Level2">Level2</th>
                        <th class="col-xs-1" data-field="Level3">Level3</th>
                    </tr>
                 </thead>

[hhurz]

Hi, did't you ask this already in issue #258 ?
This issue is neither your mistake nor a bug, but it is a missing feature, Actually it's not possible to export more than one header row when exporting to pdf using jspdf-autotable. Thats a limitation of the version of jspdf-autotable plugin, which is used by tableExport.jquery.plugin. I'm not sure if an update to a recent version of jspdf-autotable would fix this. But an update would at least require a major rework of the plugins pdf output process, what I'm not able to do. An alternative could be using pdfmake to export in pdf format instead. See also issues #139 and #245