We're trying to automatically convert currency from British pounds to US dollars so that we can then pass it to our payment provider, which only works in US dollars.
Go to our shop and look next to the USD prices listed.. There is a link to convert our prices...
a cynic writes...
Hmm... I'm more looking for something where the user doesn't need to see the conversion and I don't have to parse a webpage looking for the dollar amount.
Have a currency conversion table and populate it with a feed from oanda.com, xe.com (or similar). You'll probably have to write an import routine and the data won't be current (a few days old maybe), but its fine for most retail applications.
Addendum: "table" is a database table and you perform a lookup based on what is typed in (as opposed to html table).
xe.com's figures are reasonably up to date I believe. How you get it to populate your app I don't know.
I wouldn't try and be real time with currency conversion the rate charged depends on that charged by the credit card company and not whatever price. Unless you're being silly enough to charge in another currency.
Look up the Currency Converter Web Service @
Fog Creek Home