Exporting large records in XL format

In the below link the author has given example to handle large number of records. Here the author saves the data in "," seprated string and stream it .. and the end file is saved in CSV format.

My requirement is save the data in XL format, is it possible to convert a XL row into string format and then stream it.

http://www.codeproject.com/KB/database/ExportDataToExcelUsingCS.aspx

ASP.NET 2.0 / C#

Any help will be appreciated.

Thanks,

~ Raj
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