How to map XML to Web Dynpro context nodes?

Hi Experts,

I know there is a method in IF_WD_CONTEXT_NODE called TO_XML( ). And the method is so cool, which can export the data of the context to XML string easily.

But the question is how can I do the reverse operation?

For example, I export the data of root context node to XML string. And then how can I get the data back onto the context nodes?

Best Regards,

Guo Guo Qing