将javascript转换为PHP函数

Question

I would like to convert this javascript (which works correctly) into a PHP function, so that all this code does not have to appear in the source code of the webpage.

<script type="text/javascript">

    var images = [],
    index = 0;

    images[0] = "<a href = 'http://www.random_target1.com' target='_blank'><img src='//www.random_target1.com/random_banner.jpg' width='120' /></a>";

    images[1] = "<a href = 'http://www.random_target2.com' target='_blank'><img src='//www.random_target2.com/random_banner.jpg' width='120' /></a>";

    images[2] = "<a href = 'http://www.random_target3.com' target='_blank'><img src='//www.random_target3.com/random_banner.jpg' width='120' /></a>";

    index = Math.floor(Math.random() * images.length);
    document.write(images[index]);

</script>

I tried this PHP function in the PHP file, and thought I could call its result, from the HTML file, so only determined value would appear in HTML source code. This code broke the page, though.

public function getRandom()
{
    $images = array();
    $index = 0;

    $images[0] = "<a href = 'http://www.random_target1.com' target='_blank'><img src='//www.random_target1.com/random_banner.jpg' width='120' /></a>";

    $images[1] = "<a href = 'http://www.random_target2.com' target='_blank'><img src='//www.random_target2.com/random_banner.jpg' width='120' /></a>";

    $images[2] = "<a href = 'http://www.random_target3.com' target='_blank'><img src='//www.random_target3.com/random_banner.jpg' width='120' /></a>";

    $index = Math.floor(Math.random() * $images.length);
    return $images[$index];
}   

Answer 1

$images = array(
"<a href = 'http://www.random_target1.com' target='_blank'><img src='//www.random_target1.com/random_banner.jpg' width='120' /></a>",
 "<a href = 'http://www.random_target1.com' target='_blank'><img src='//www.random_target1.com/random_banner.jpg' width='120' /></a>",
 "<a href = 'http://www.random_target1.com' target='_blank'><img src='//www.random_target1.com/random_banner.jpg' width='120' /></a>"
);
$index = rand(0, count($images)-1);

echo $images[$index];

Answer 2

Note I use mt_rand instead of rand. It's generally considered a better random number function.

<?php 
$images = array();

$images[0] = "<a href = 'http://www.random_target1.com' target='_blank'><img src='//www.random_target1.com/random_banner.jpg' width='120' /></a>";

$images[1] = "<a href = 'http://www.random_target2.com' target='_blank'><img src='//www.random_target2.com/random_banner.jpg' width='120' /></a>";

$images[2] = "<a href = 'http://www.random_target3.com' target='_blank'><img src='//www.random_target3.com/random_banner.jpg' width='120' /></a>";

$randIndex = mt_rand(0,sizeof($images)-1);

echo $images[$randIndex];
?>