PHP Mongodb not updating array - php

Question

I am not sure why but I am getting this error
Fatal error: Call to a member function update() on a non-object in /home/XXXXXXXXXXXXXXXXX/classes/core.php on line 22
On that page I have this
public function updatemongo($from,$data)
{
$this->db = $m->exchange_rates;
$collection = $this->db->exchangeDB;
$collection->update(array("from" => $from), $data);
}
this is how I am calling this function
foreach ($currencies as $to)
{
if($from != $to)
{
$url = 'http://finance.yahoo.com/d/quotes.csv?f=l1d1t1&s='.$from.$to.'=X';
$handle = fopen($url, 'r');
if ($handle) {
$result = fgetcsv($handle);
fclose($handle);
}
$newdata = array('$set' => array("exchangehistory.{$result[1]}.{$result[2]}" => array("to" => $to, "rate" => $result[0], "updated" => $result[2])));
$fetch->updatemongo($from,$newdata);
$newdata = array('$set' => array("currentexchange" => array("to" => $to, "rate" => $result[0], "updated" => $result[2])));
$fetch->updatemongo($from,$newdata);
}
}
and yes the file needing to access this is also has require_once("core.php");
Please let me know why this is not working.

Answer 1

The updatemongo() function doesn't have access to the $m variable. Please pass it to the function like this:
$fetch->updatemongo($m, $from, $newdata);
And change your function definition to:
public function updatemongo($m, $from, $data)
{
Alternatively, you can set the m property of the object to the connection after you've created it. For example with:
public function __construct)
{
$this->m = new Mongo();
}
...
public function updatemongo($from, $data)
{
$this->db = $this->m->exchange_rates;
$collection = $this->db->exchangeDB;
$collection->update(array("from" => $from), $data);
}
Or perhaps you can just use $this->exchange_rates already above... in any case, you're not making $m available to the function.

Answer 2

Looks like a typo : the object "$m" is not instantiated in function updatemongo()
Either create it here or gain access with global $m; if it exists.

Answer 3

$this->db->exchangeDB contains null or similar when it gets placed into $collection? It's hard to tell for us since we don't know where that variable gets instantiated.
$collection->update(array("from" => $from), $data);
is the cause of your error and the error is clear: $update is not an object. otherwise it would complain "PHP Fatal error: Call to undefined method YourClass::yourMethod() in /my/php/file.php on line xx"