Greetings to all,
I am an old guy who have started to learn html, css and php.
Is there any difference using comma vs punctuation when concatenate?
For example:
[php]
$number = 5;
$text = “hello”;
echo “Coool string”, " and another string" . " " . $number, 5 * 44;
[/php]
Both seems to work but all books I have started to read all use punctuation…but why not use comma?
I have honestly never seen a comma used this way and I’m surprised it doesn’t issue any warnings.
It’s not even listed as a string operator:
http://www.php.net/manual/en/language.operators.string.php
You should certainly stick with the period. Here is a good link to learn about strings and the various ways to build them:
http://php.net/manual/en/language.types.string.php
I also recommend everyone develop a coding standard. I personally use the PEAR standards:
Ah, this does seem to be only related to the echo function so it should never be used IMO.
For example:
[php]
$output = “Coool string”, " and another string" . " " , $number, 5 * 44;
echo $output;
[/php]
This issues “Parse error: syntax error, unexpected ‘,’”
Just for further clarification…
echo doesn’t do any concatenation, so take this for example:
[php]
$a = "This is a " . “concatenated” . “string”;
$b = "This is a " . “concatenated” . “string”;
$c = "This is a " . “concatenated” . “string”;
echo $a;
echo $b;
echo $c;
[/php]
You could instead do
[php]
echo $a, $b, $c;
[/php]