I have been trying to save html data in excel format(export to excel functionality basically) in PHP. I achieved that by changing header to
header("Content-type: application/vnd.ms-excel");
header("Content-Disposition: attachment; filename=$filename");
header("Pragma: no-cache");
header("Expires: 0");
But on opening the file, it shows a warning for above excel 2003 applications. So can I save the excel in 2008 or 2010 format just by modifying the header or do I have to go for other frameworks providing this feature like "PHPExcel" or something. And yes, I am using CodeIgniter for my website
Thanks in advance.