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PHP

Posted by Kohane Kagami
Kohane Kagami
12,390 Points

What does this mean? $output = $number . $output;

Here is the quiz and the answer is 321. What does　”$output = $number . $output;” mean?

What does the following code display?

＜?php

$numbers = array(1,2,3,4);

$total = count($numbers);

$sum = 0;

$output = "";

$i = 0;

foreach($numbers as $number) {

$i = $i + 1;

if ($i < $total) {

    $output = $number . $output;

}

}

echo $output;

?＞

2 Answers

Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,074 Points
Carlos Federico Puebla Larregle
Carlos Federico Puebla Larregle
21,074 Points

The "." (dot) is used for concatenation, so in this case you are going to assign the concatenation between the "$number" variable and the variable "$output" to the variable "$output".

Here's another example of concatenation using the "." (dot).

<?php
$a = "Hello ";
$b = $a . "World!"; // now $b contains "Hello World!"

$a = "Hello ";
$a .= "World!";     // now $a contains "Hello World!"
?>

I hope that helps a little bit.

Kohane Kagami
Kohane Kagami
12,390 Points

Thank you very much. :) I could understand well. If you have facebook account, please add me. https://www.facebook.com/GangstaCatAkidsuki

Matthew Smart
Matthew Smart
12,567 Points
Matthew Smart
Matthew Smart
12,567 Points

$output = $number . $output;

$output is first made an empty string by $output = ''";

Now what we are saying it that the new $output is the $number and the current $output.

So if $output = 1

And i say $output = $output .'-'. $output;

then when i echo $output it would say 1-1

the dot is concatenating the values together.

Kohane Kagami
Kohane Kagami
12,390 Points

Thank you very much. :) I really appreciate it. If you have facebook account, please add me. https://www.facebook.com/GangstaCatAkidsuki