循环使用通用名称的变量

Question

At first glance I think you can get what I'm trying to do. I want to loop though variables with the same name but with a numerical prefix. I also had some confusion about the kind of loop I should use, not sure if a "for" loop would work. The only thing is I can't wrap my head around how php could interpret "on the fly" or fabricated variable. Ran into some trouble with outputting a string with a dollar sign as well. Thanks in advance!

$hello1 = "hello1";
$hello2 = "hello2";
$hello3 = "hello3";
$hello4 = "hello4";
$hello5 = "hello5";
$hello6 = "hello6";
$hello7 = "hello7";
$hello8 = "hello8";
$hello9 = "hello9";
$hello10 = "hello10";

for ( $counter = 1; $counter <= 10; $counter += 1) {
    echo $hello . $counter . "<br>";
}

Answer 1

It's generally frowned upon, since it makes code much harder to read and follow, but you can actually use one variable's value as another variable's name:

$foo = "bar";
$baz = "foo";

echo $$baz; // will print "bar"

$foofoo = "qux";
echo ${$baz . 'foo'}; // will print "qux"

For more info, see the PHP documentation on variable Variables .

However, as I already mentioned, this can lead to some very difficult-to-read code. Are you sure that you couldn't just use an array instead?

$hello = array(
    "hello1",
    "hello2",
    // ... etc
);

foreach($hello as $item) {
    echo $item . "<br>";
}

Answer 2

Try ${"hello" . $counter} ${"hello" . $counter}

$a = "hell";
$b = "o";
$hello = "world";
echo ${$a . $b};

// output: world

Answer 3

You can use variable variables as:

for ( $counter = 1; $counter <= 10; $counter += 1) {
        echo ${'hello' . $counter } , '<br>';
}

Answer 4

as I guess u not even need to declare $hello1 = "hello1". coz the $counter is incrementing the numbers by its loop.

<?php 
for ( $counter = 1; $counter <= 10; $counter += 1) {
echo 'hello' . $counter . "\n";
}
?>

so this is enough to get the output as you want.

the output will be:-

hello1
hello2
hello3
hello4
hello5
hello6
hello7
etc...