One option is as follows:
1. Create a new excel file using
Microsoft.Office.Interop.Excel
.
2. Open each of the excel file and write contents to the newly created excel file.
3. Save the newly created excel file.
4. Generate the PDF file from the newly created excel file.
An example for using
Microsoft.Office.Interop.Excel
is given here.
http://msdn.microsoft.com/en-us/library/ms173186(v=vs.80).aspx[
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