How can I use PHP to generate real Excel files? PS: Do not use Phpexcel card

How do I use PHP to generate a real Excel file? PS: Do not use phpexcel too card!
Recently, there are projects that need to export data in large batches to Excel files, the early use of phpexcel, when the amount of data is less than the line! But in large quantities of data such as the 10,000 line, the memory consumed is too high, it is easy to overflow!

Using the Generate XML as an XLS format can be very efficient, but it will pop up when you open the file with the message "You're trying to open the XX." XLS ' format is inconsistent with the format specified by the file extension ... " It's very annoying! Want to ask how can you remove this hint? How to make a simple implementation of the real Excel file, but also can set a simple cell format!

Trouble knowing under the guidance! Thank you! ~ There are thick points of dedication! ~

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Using the Generate XML as an XLS format can be very efficient, but it will pop up when you open the file with the message "You're trying to open the XX." XLS ' format is inconsistent with the format specified by the file extension ... "

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CSV format can be opened directly with Excel, without any hint, do not know whether it meets your requirements?

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