如何在PHP中为数字添加逗号（会话值）

Question

I would like to change this:

4000

to this

4,000

I am using this code

<?php echo number_format(($_SESSION["result"]),",")  ; ?>

But its printing nothing...

Answer 1

Have a look at the parameters shown here.

<?php echo number_format(($_SESSION["result"]), 3,",", "."); ?>