PHP change output depending how many variables exist

Question

Apologies if this is a simple question and/or it's nonsensical.

What I'm trying to do is change the output of a string, based on 2 simple variables.

This is the original variable;

$src = 'http://example.org';

And I have the following option variables which pull data from a Wordpress shortcode (If it exists);

$bg = $attr['background'];
$col = $attr['color'];

What I want to achieve is this, if neither of the option variables have values the original variable remains unchanged.

If only one of the option variables exist, the original variable's value becomes;

http://example.org?background='.$bg.'

or

http://example.org?color='.$col.'

Depending on which one has a value.

If both option variables have values, the original value needs to become;

http://example.org?background='.$bg.'&color='.$col.'

Can someone point me in the right direction on this please? It would be greatly appreciated.

Mark · Accepted Answer · 2018-05-01 10:37:04Z

2

Try this:

$src = 'http://example.org';
$start = '?';

if(isset($attr['background'])) {
    $src .= $start . 'background=' . $attr['background'];
    $start = '&';
}

if(isset($attr['color'])) $src .= $start . 'col=' . $attr['color'];

Should be self-explanatory, but we slowly build up the $src variable depending on whether a background or color is set.

edited May 1, 2018 at 10:37

answered May 1, 2018 at 10:33

Mark

1,8723 gold badges18 silver badges31 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

user7236046 · Accepted Answer · 2018-05-01 10:40:49Z

2

You can do this easily using the add_query_arg() function built into WordPress.

$url = 'http://example.org';

if ( isset($attr['background']) ) {

    add_query_arg( 'background', $attr['background'], $url );

}

if ( isset($attr['color']) ) {

    add_query_arg( 'color', $attr['color'], $url );

}

answered May 1, 2018 at 10:40

user7236046

Comments

Jeff · Accepted Answer · 2018-05-01 10:49:34Z

1

Here's a small function that creates the params out of a given parameter-array as you have it:

<?php
// the settings:
$attr = [];
$attr['background'] = "#ededed";
$attr['color'] = "red";
#$attr['otherparam'] = "123456";
$url = 'http://example.org';

// the method
function createParamsString($params) {
    $p = [];
    foreach($params as $key=>$value) { 
       $p[]  = $key."=".urlencode($value);
    }
    return implode("&", $p);
}

// usage:
$paramsString = createParamsString($attr);

$url = !empty($paramsString) ? $url."?".$paramsString : $url;

echo $url;

This way it's modular. You can just add entries to $attr an all is good. urlencode is important if you have a values like #EDEDED for background.

answered May 1, 2018 at 10:49

Jeff

6,9611 gold badge19 silver badges34 bronze badges

Collectives™ on Stack Overflow

PHP change output depending how many variables exist

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related