function get_currency_rate

Simple, yet effective way to get currency rate from yahoo finance service. Cache the results, or you will get ban from yahoo.



function get_currency_rate($from, $to){
 
    $json = get_contents("http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.xchange%20where%20pair%20in%20(%22".$from.$to."%22)&format=json&env=store://datatables.org/alltableswithkeys&callback=");
    $json = json_decode($json);
    $rate = $json->query->results->rate->Rate;
    if($rate < 0.001){
        // try again reversal
        $json = get_contents("http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.xchange%20where%20pair%20in%20(%22".$to.$from."%22)&format=json&env=store://datatables.org/alltableswithkeys&callback=");
        $json = json_decode($json);
        $rate = $json->query->results->rate->Rate;
        if($rate != 0.00){
            $rate = 1/$rate;
        }
    }
    return $rate;
}