How to connect a webservice to get currency values in Objective-C

I would like to get values of currencies on my iphone application whe it starts. How to do it? what webservice? I found a code in php using google request as 开发者_JAVA技巧"1 USD FOR EURO" that returns the currency value (try this link text) but how to get the returning value in OjC and put it into a variable? thank you

The exchange rate is not a world constant - it varies from one exchange office to another. Try finding a bank, or some kind of a financial institution, that publishes their rates as a Web service.

I found this www.ecb.int/stats/eurofxref/eurofxref-daily.xml

Now I'm studing sdk in orther to know how to read xml files