在PHP中处理服务器上的Excel公式

Question

I have a rather complex spreadsheet formula. Right now I am using PHPExcel to load the spreadsheet into memory, and I set the cell values of the formula input to the values from a front-end form (using ajax), get the calculated result and send it back to the client.

Is this the best way to this? Or should the formulas be converted to pure php?

If this is an okay method, I have concerns regarding concurrency and memory usage.

The spreadsheet isn't that large, less than 1000 cells. How can I calculate the threshold for concurrency (people clicking calculate on the front end) and memory usage on the server?

What steps can I take to optimise this algorithm (caching for example) whilst balancing performance?

Answer 1

You're going to have problems doing this as an ajax request for large numbers of concurrent users, because these http requests have no persistence, so you need to load the spreadsheet file for every request. What it does guarantee is that each request runs independently with its own copy of the spreadsheet, so no individual user's request will affect any of the other users requests.

The other extreme is to take all the Excel logic and rewrite it in PHP. You don't give any indication of the complexity of your spreadsheet formulae, so it's difficult to judge how complex a task this would be.

A third option would be to use only PHPExcel's calculation engine, feeding it with the form values and formulae directly. This eliminates the time and memory overheads of loading the spreadsheet file with every request, so could be the easiest and most efficient option. You can find an example of this in the Quadratic2.php example file in the /Tests directory of the PHP distribution.