CodeIgniter Setting config item that is in array - codeigniter

Question

So I just started using CodeIgniter... and got stuck in setting config item
I have read that replacing the value of a config item is as easy as this:
$this->config->set_item('item_name', 'item_value');
But what if I want to set a config item that is part of an array of config items... like this one:
$api_config = $this->config->load('api'); //loading the created configuration under config folder
api.php
$facebook['app_id'] = '123213213';
$facebook['api_key'] = '123123WERWERWE123123';
$config['facebook'] = $facebook;
and I want to dynamically replace app_id.

Answer 1

Sure you can do it, but you'll need to manually unwrap/rewrap the config item. For example, given this config file:
$f['a'] = "1";
$f['b'] = "2";
$config['t'] = $f;
And this controller function:
function t()
{
var_dump($this->config->item("t"));
echo "<br>";
$v = $this->config->item("t");
$v['a'] = "3";
$this->config->set_item('t', $v);
var_dump($this->config->item("t"));
}
You will get this output:
array(2) { ["a"]=> string(1) "1" ["b"]=> string(1) "2" }
array(2) { ["a"]=> string(1) "3" ["b"]=> string(1) "2" }
One thing to note: the actual config value in the file hasn't changed: you will need to re-apply your change on each request.

Answer 2

Unfortunately, you can't do that as you have things right now.
A look at the code in question:
// from CI 2, CI 1 has no differences which will effect the current situation
include($file_path);
if ( ! isset($config) OR ! is_array($config))
{
if ($fail_gracefully === TRUE)
{
return FALSE;
}
show_error('Your '.$file_path.' file does not appear to contain a valid configuration array.');
}
if ($use_sections === TRUE)
{
if (isset($this->config[$file]))
{
$this->config[$file] = array_merge($this->config[$file], $config);
}
else
{
$this->config[$file] = $config;
}
}
else
{
$this->config = array_merge($this->config, $config);
}
As you can see, the only value which is picked up from the config file is $config. CI pretty much discards everything else. You should not be able to access that value through config for reading or writing.
Your options are that you can have a facebook config file, you can store the facebook array as a value in the $config variable in the api config file, or you can store the value as some special key like 'facebook_app_id' in the same file. You'll have to decide which option is best for your needs, but I would be inclined to store the value as 'facebook_app_id'.

Answer 3

$this->config->load('api', true);//load config first
//begin set new value
$this->config->set_item('app_Ckey',‘your new value’);
$this->config->set_item('app_id',‘your new value’);
$this->load->library('api');
echo $this->config->item('app_Ckey');