Question

I want to access a variable that is either called $item1, $item2 or $item3.

I want to access this variable inside a for loop where $i is ++ every time. using $item.$i or something similar. However using that code means that I am trying to join the contents of two variables, and there is no variable called $item.

Answer 1

Arrays: A Better Method

While PHP does permit you to build dynamic variable names from various other values, you probably shouldn’t in this case. It seems to me that an array would be more appropriate for you:

$items = array( 0, 12, 34 );

You could then access each value individually:

echo $items[0]; // 0
echo $items[1]; // 12

Or loop over the entire set:

foreach ( $items as $number ) {
  echo $number; // 1st: 0, 2nd: 12, 3rd: 34
}

Merging Multiple Arrays

You indicated in the comments on the OP that $item1 through $item3 are already arrays. You could merge them all together into one array if you like with array_merge(), demonstrated below:

$item1 = array( 1, 2 );
$item2 = array( 3, 4 );
$item3 = array( 5, 6 );

$newAr = array_merge( $item1, $item2, $item3 );

print_r( $newAr );

Which outputs:

Array
(
  [0] => 1
  [1] => 2
  [2] => 3
  [3] => 4
  [4] => 5
  [5] => 6
)

If You Must: Dynamic Variable Names

For completeness, if you were to solve your problem by dynamically constructing variable names, you could do the following:

$item1 = 12;
$item2 = 23;
$item3 = 42;

for ( $i = 1; $i <= 3; $i++ ) {
  echo ${"item".$i} . PHP_EOL;
}