How to pass multiple checkbox values to php [duplicate] - php

Question

This question already has answers here:
Get $_POST from multiple checkboxes
(5 answers)
Getting checkbox values on submit
(10 answers)
Closed 3 years ago.
Currently i have a HTML form that collects some metadata about some files, and each user as to fill some fields. I want to register some keywords about the data. I could ask them to write the keywords by hand on a normal text box, but i would prefer to have a list of checkboxes of about 10/15 values.
Then i need to pass only the checked values to a PHP file, using $_POST. My problem is that i assign a variable to those values, and then i call that variable in a DOM event. I´m generating a XML file, and currently i have the HTML ready to register these keywords in text input. I understand how to create the checkboxes, and pass them as an array to PHP., by reading other questions here. But i can´t understand how to pass this array to a $dom->createElement situation, and preferably separated by commas.
PHP
//Pull data from HTML form
$keywordsString = $_POST['keywords'];
// Creates xml document
$dom = new DOMDocument();
$dom->encoding = 'utf-8';
$dom->xmlVersion = '1.0';
$dom->formatOutput = true;
$xmlFileName = 'example_example.xml';
// Adds metadata to xml
$metadata = $dom->createElement('MD_Metadata');
$idInfo = $dom->createElement('identificationInfo');
$descriptiveKeywords = $dom->createElement('descriptiveKeywords');
$CharacterString = $dom->createElement('CharacterString', $keywordsString);
$descriptiveKeywords->appendChild($CharacterString);
$idInfo->appendChild($descriptiveKeywords);
$metadata->appendChild($idInfo);
$dom->appendChild($metadata);
$dom->save($xmlFileName);
I can´t figure out how to pass checkbox values to that $keywordsString , but separated by commas. The rest i can understand and write, using the other questions about this kind of issue.
Thanks in advance for all help provided.

Answer 1

Your html should look like this:
<form action="" method="post">
<input name="choice[]" type="checkbox" value="1" />
<input name="choice[]" type="checkbox" value="2" />
<input name="choice[]" type="checkbox" value="3" />
<input name="choice[]" type="checkbox" value="4" />
<input type="submit" value="order" />
</form>
In PHP, you can iterate over using foreach loop. Place the below code at the top of your html form:
A small note from basics, when posting data via post method, you need to apply Post redirect get design pattern to prevent form re-submissions.
If the data you are sending is not sensitive, you can do it via get request.
<?php
if($_POST):
foreach($_POST['choice'] as $val)
{
echo $val . "<br>";
}
endif;
?>