Fastest way to implode an associative array with k

Question

I'm looking for a fast way to turn an associative array in to a string. Typical structure would be like a URL query string but with customizable separators so I can use '&' for xhtml links or '&' otherwise.

My first inclination is to use foreach but since my method could be called many times in one request I fear it might be too slow.

<?php
$Amp = $IsXhtml ? '&amp;' : '&';
$Parameters = array('Action' => 'ShowList', 'Page' => '2');
$QueryString = '';
foreach ($Parameters as $Key => $Value)
        $QueryString .= $Amp . $Key . '=' . $Value;

Is there a faster way?

Answer 1

One way is using print_r(array, true) and it will return string representation of array

Answer 2

If you're not concerned about the exact formatting however you do want something simple but without the line breaks of print_r you can also use json_encode($value) for a quick and simple formatted output. (note it works well on other data types too)

$str = json_encode($arr);
//output...
[{"id":"123","name":"Ice"},{"id":"234","name":"Cake"},{"id":"345","name":"Pie"}]

Answer 3

This is the most basic version I can think of:

public function implode_key($glue = "", $pieces = array())
{
    $keys = array_keys($pieces);
    return implode($glue, $keys);
}

Answer 4

This is my solution for example for an div data-attributes:

<?

$attributes = array(
    'data-href'   => 'http://example.com',
    'data-width'  => '300',
    'data-height' => '250',
    'data-type'   => 'cover',
);

$dataAttributes = array_map(function($value, $key) {
    return $key.'="'.$value.'"';
}, array_values($attributes), array_keys($attributes));

$dataAttributes = implode(' ', $dataAttributes);

?>

<div class="image-box" <?= $dataAttributes; ?> >
    <img src="http://example.com/images/best-of.jpg" alt="">
</div>