I'm trying to define three empty variables through a foreach loop to make my code cleaner. This is what I've tried, however I see the error:
Notice: Undefined variable: hi
foreach(['$hi','$bye','$hello'] as $key) {
$key = "";
}
$hi .= "hello";
When I remove the foreach loop and simply define each empty variable one by one, like this, it works:
$hi = "";
$bye = "";
$hello = "";
You're assigning to $key, not to the variable that's named by it. To indirect through a variable, you need to use $$key. But the value of the variable shouldn't include the $, just the variable name.
foreach (['hi', 'bye', 'hello'] as $key) {
$$key = "";
}
$hi .= "hello";
However, if you ever find yourself using variable variables like this, you're almost certainly doing something wrong. You should probably be using an associative array instead.
You have strings which are saved in $key. So the value of $key is a string and you set it to "".
Later you want to append something to a variable you never used.
Try to remove the ' and write
foreach([$hi, $bye, $hello] as $key) {
Generally thats not the best way to initialise multiple variables. Try this
Easier way:
list($hi, $bye, $hello) = "";
$hi = $bye = $hello = "";?
$hi = $bye = $hello = ""; is better.foreach creates a new array variable in memory, so you only clear these values inside the array in memory which is useless out of the foreach sentence. the best way is:
$h1=$bye=$hello="";
I didn't think that a foreach process will work more fast than a Simple equal (=), foreach function uses more CPU resources than a simple =. That's because the math CPU exists.
