Summary

In this chapter you looked at ways to generate or use documents with a high level of structure. You saw how markup can generate HTML and XML documents and how the DOM extension can make creating XML documents much easier. We also touched on the new SimpleXML extension that can read and parse XML documents from the local hard drive or a remote server.

In addition, you tackled more advanced services and how to use XML with them. You looked at a common format for site syndication, RSS. This format is widely used to create news feeds, and we showed how you can build a simple web-based reader. After RSS you learned about WDDX and how you can use it to exchange complex data between servers or applications. Finally, you learned about SOAP and its ability to provide both data and a data definition, allowing the client to consume web services without prior knowledge about the service.