Currency Conversion using PHP

Question

I'm looking for a way to convert any amount from one currency to another on a website. The user would enter something like '100' and select USD as the currency, and then chooses Australian or Canadian dollars as the currency to convert to. When he clicks the 'Convert' button, I'd like to convert that amount automatically, through some API, and show him the amount in the currency he chose to convert to.

Any ideas?

Answer 1

This method is using Yahoo currency API Full tutorial : Currency Converter in PHP, Python, Javascript and jQuery

function currencyConverter($currency_from, $currency_to, $currency_input) {
    $yql_base_url = "http://query.yahooapis.com/v1/public/yql";
    $yql_query = 'select * from yahoo.finance.xchange where pair in ("' . $currency_from . $currency_to . '")';
    $yql_query_url = $yql_base_url . "?q=" . urlencode($yql_query);
    $yql_query_url .= "&format=json&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys";
    $yql_session = curl_init($yql_query_url);
    curl_setopt($yql_session, CURLOPT_RETURNTRANSFER, true);
    $yqlexec = curl_exec($yql_session);
    $yql_json =  json_decode($yqlexec, true);
    $currency_output = (float) $currency_input * $yql_json['query']['results']['rate']['Rate'];

    return $currency_output;
}

$currency_input = 2;
//currency codes : http://en.wikipedia.org/wiki/ISO_4217
$currency_from = "USD";
$currency_to = "INR";
$currency = currencyConverter($currency_from, $currency_to, $currency_input);

echo $currency_input . ' ' . $currency_from . ' = ' . $currency . ' ' . $currency_to;