PHP: Basic curl example

Basic curl example

Once you've compiled PHP with cURL support, you can begin using the cURL functions. The basic idea behind the cURL functions is that you initialize a cURL session using the curl_init(), then you can set all your options for the transfer via the curl_setopt(), then you can execute the session with the curl_exec() and then you finish off your session using the curl_close(). Here is an example that uses the cURL functions to fetch the example.com homepage into a file:

Example #1 Using PHP's cURL module to fetch the example.com homepage


<?php

$ch = curl_init("http://www.example.com/");
$fp = fopen("example_homepage.txt", "w");

curl_setopt($ch, CURLOPT_FILE, $fp);
curl_setopt($ch, CURLOPT_HEADER, 0);

curl_exec($ch);
if(curl_error($ch)) {
    fwrite($fp, curl_error($ch));
}
curl_close($ch);
fclose($fp);
?>

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User Contributed Notes 1 note

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Roberto Braga ¶

8 years ago


It is important to notice that when using curl to post form data and you use an array for CURLOPT_POSTFIELDS option, the post will be in multipart format



<?php

$params=['name'=>'John', 'surname'=>'Doe', 'age'=>36];

$defaults = array(

CURLOPT_URL => 'http://myremoteservice/', 

CURLOPT_POST => true,

CURLOPT_POSTFIELDS => $params,

);

$ch = curl_init();

curl_setopt_array($ch, ($options + $defaults));

?>

This produce the following post header:



--------------------------fd1c4191862e3566

Content-Disposition: form-data; name="name"



Jhon

--------------------------fd1c4191862e3566

Content-Disposition: form-data; name="surnname"



Doe

--------------------------fd1c4191862e3566

Content-Disposition: form-data; name="age"



36

--------------------------fd1c4191862e3566--



Setting CURLOPT_POSTFIELDS as follow produce a standard post header



CURLOPT_POSTFIELDS => http_build_query($params),



Which is:

name=John&surname=Doe&age=36



This caused me 2 days of debug while interacting with a java service which was sensible to this difference, while the equivalent one in php got both format without problem.

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