Google Currency Converter

Question

如何使此货币转换器正常工作？

通过Google API

function convertCurrency($amount, $from, $to){
    $data = file_get_contents("https://www.google.com/finance/converter?a=$amount&from=$from&to=$to");
    preg_match("/<span class=bld>(.*)<\/span>/",$data, $converted);
    $converted = preg_replace("/[^0-9.]/", "", $converted[1]);
    return number_format(round($converted, 3),2);
}

echo convertCurrency("10.00", "GBP", "USD");