Incrementing / Decrementing Operators
++
increment operator
--
decrement operator
Example Name Effect
---------------------------------------------------------------------
++$a Pre-increment Increments $a by one, then returns $a.
$a++ Post-increment Returns $a, then increments $a by one.
--$a Pre-decrement Decrements $a by one, then returns $a.
$a-- Post-decrement Returns $a, then decrements $a by one.
These can go before or after the variable.
If put before the variable, the increment/decrement operation is done to the variable first then the result is returned. If put after the variable, the variable is first returned, then the increment/decrement operation is done.
For example:
$apples = 10;
for ($i = 0; $i < 10; ++$i) {
echo 'I have ' . $apples-- . " apples. I just ate one.\n";
}
Live example
In the case above ++$i
is used, since it is faster. $i++
would have the same results.
Pre-increment is a little bit faster because it really increments the variable and after that 'returns' the result. Post-increment creates a special variable, copies there the value of the first variable and only after the first variable is used, replaces its value with second's.
However, you must use $apples--
, since first, you want to display the current number of apples, and then you want to subtract one from it.
You can also increment letters in PHP:
$i = "a";
while ($i < "c") {
echo $i++;
}
Once z
is reached aa
is next, and so on.
Note that character variables can be incremented but not decremented and even so only plain ASCII characters (a-z and A-Z) are supported.
Stack Overflow Posts:
Best Practice
As mentioned in the comment to the first answer, the best practice is to use the PHP constant PHP_EOL which represents the current system's EOL (End Of Line).
$skuList = explode(PHP_EOL, $_POST['skuList']);
PHP provides a lot of other very useful constants that you can use to make your code system independent, see this link to find useful and system independent directory constants.
Warning
These constants make your page system independent, but you might run into problems when moving from one system to another when you use the constants with data stored on another system. The new system's constants might be different from the previous system's and the stored data might not work anymore. So completely parse your data before storing it to remove any system dependent parts.
UPDATE
Andreas' comment made me realize that the 'Best Practice' solution I present here does not apply to the described use-case: the server's EOL (PHP) does not have anything to do with the EOL the browser (any OS) is using, but that (the browser) is where the string is coming from.
So please use the solution from @Alin_Purcaru (three down) to cover all your bases (and upvote his answer):
$skuList = preg_split('/\r\n|\r|\n/', $_POST['skuList']);
Best Answer
Richard is saying this:
...after PHP-parsing becomes this:
I just add an extra newline manually, like this:
...giving this: