How to create a password protected table from PHP?

Question

How to create a password protected table from PHP?

I tried the PHPExcel library from http://phpexcel.codeplex.com/

PHPExcel offers 3 levels of security: document security, page security, and cell security.

Document security allows you to set a password in a complete spreadsheet, allowing you to make changes only when you enter this password. But the user can open the spreadsheet and view the contents without a password.

And I also tried Spreadsheet_Excel_Writer, but did not find a solution for this. Spreadsheet_Excel_Writer offers only worksheet level protection, not file protection.

Does anyone know other PHP Excel authors who offer file protection where users cannot even open an Excel file without a password?

Answer 1

Protecting a complete workbook involves encrypting workbook data, and the encryption algorithm used for this is one side of the Excel format that I have not seen in any of the available documents. Of course, not one of the PHP writer libraries supports this: the only way I know this (inside the book itself) is to use the COM extension to create your book.