PHP set multipart or form data - php

Question

I am trying to work with a html file using the following but I am having an issue doing it with the PHP api. I already have the files ready on the server but I cannot figure out how to set the multipart/form data using the following code to do the conversion. Lets say I have a html file in the same folder how do I use it in the following code for conversion.
Code for conversion :
<?php
//set POST variables
$fields = array('from' => 'markdown',
'to' => 'pdf',
'input_files[]' => "#/".realpath('markdown.md').";type=text/x-markdown; charset=UTF-8"
);
//open connection
$ch = curl_init();
curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-type: multipart/form-data"));
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_POSTFIELDS, $fields);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); //needed so that the $result=curl_exec() output is the file and isn't just true/false
//execute post
$result = curl_exec($ch);
//close connection
curl_close($ch);
?>

Answer 1

Since PHP 5.5, the # format for specifying a file path is no longer valid, and the value will be sent as a raw string. Instead try curl_file_create. Also, regardless of version, don't forget to set CURLOPT_POST variable to true as well. This code also assumes you have read access to the file being uploaded.
<?php
$url = 'http://c.docverter.com/convert';
$fields = [
'from' => 'markdown',
'to' => 'pdf',
'input_files[]' => (PHP_VERSION_ID < 50500) ? '#' . realpath('markdown.md') : curl_file_create('markdown.md')
];
$result_file = 'uploads/result.pdf';
//open connection
$ch = curl_init($url);
curl_setopt_array($ch, [
CURLOPT_POST => true,
CURLOPT_POSTFIELDS => $fields,
CURLOPT_RETURNTRANSFER => true
]);
$result = curl_exec($ch);
curl_close($ch);
file_put_contents($result_file, $result);