用vb.net编写的读写xml文件.对学习xml很有帮助-prepared using vb.net write xml document. Helpful to learn xml

XML文档的结构是一个树形等级结构。文档必须有一个唯一的根结点，根节点包含所有其它节点。下面我们举一个较为完整的例子-XML document structure is a hierarchical structure tree. Document must have a unique root node, root node contains all the other nodes. Below we give a more complete example