How SOAP and REST work with XML/JSON response?

Question

This is one very common question asked again and again on stack overflow and I read so many answers about this but I am still bit confused.

I need to call the webservice

Answer 1

1) SOAP responses must be XML, and to return other formats you need to either embed them in the response XML (inefficient) or use SOAP attachments (difficult). SOAP responses are contained in a soap envelope tag, and there is usually an associated wsdl. If the XML you show is all you're getting, then it may not be a SOAP service. I see links in the XML so that is a good sign that they had REST in mind.

2) I haven't heard of ASIHTTP. A quick google, and it looks like its a third party library that wraps the http interfaces in iOS. It looks like you would use that to help you make the http requests, although I would suggest that it might not be necessary; you should evaluate using the http libraries directly.

3) You need to parse it somehow. You can do it by hand, but that is generally a really bad idea. XML can come in many forms and still have the same meaning, and if you don't support all forms your application could break in the future if the web service provider began to format their XML differently, even if its semantics were the same. You would use an XML api to read the XML. The DOM api will read it into a tree form for you, and you can use XPath to extract information out of the tree.