XML学习笔记(七)：XPath数据模式

• XPath数据模式依赖存System.Xml.XPath命名空间的XPathNavigator类。
• XPathNavigator类是一个抽象类，是一个以指针方式为基础的浏览XML数据的模式，它允许你对XML文件进行编辑。
• 你可以从任何实现了IXPathNavigable接口的类获得XPathNavigator类的一个实例。XmlDocument和XPathDocument就是实现了这个接口的类。
• XmlDocument返回的XML是可编辑的，XPathDocument返回对象是只读的。

创建XPathNavigator对象：

 

  //功能性示例代码：
private void button1_Click(object sender, EventArgs e)
    {
        XPathNavigator navigator = null;
        if (radioButton1.Checked)
        {
            //XmlDocument类创建XPathNavigator对象
            XmlDocument doc = new XmlDocument();
            doc.Load(Application.StartupPath + @"/employees.xml");
            navigator = doc.CreateNavigator();
        }
        else
        {
            //XmlPathDocument类创建XPathNavigator对象
            XPathDocument doc = new XPathDocument(Application.StartupPath + @"/employees.xml");
            navigator = doc.CreateNavigator();
        }
        MessageBox.Show("Navigator created successfully!");
    }

通过XPathNavigator来浏览XML文档

 

   1:   protected void Button1_Click(object sender, EventArgs e)

   2:      {

   3:          XPathDocument doc =new XPathDocument(xmlFilePath);

   4:          XPathNavigator navigator = doc.CreateNavigator();

   5:          navigator.MoveToRoot();

   6:          navigator.MoveToFirstChild();        

   7:          TreeNode root = TreeView1.Nodes.Add("Employees");

   8:          while (navigator.MoveToNext())

   9:          {

  10:              if (navigator.HasChildren)

  11:              {

  12:                  navigator.MoveToFirstChild();

  13:                  do

  14:                  {

  15:                      string id = navigator.GetAttribute("employeeid", "");

  16:                      TreeNode empnode = new TreeNode("Employee ID :" + id);

  17:                      root.Nodes.Add(empnode);

  18:                      navigator.MoveToFirstChild();

  19:                      do

  20:                      {

  21:                          string name = navigator.Name;

  22:                          TreeNode node = new TreeNode(name + " : " + navigator.Value);

  23:                          empnode.Nodes.Add(node);

  24:                      } while (navigator.MoveToNext());

  25:                      navigator.MoveToParent();

  26:                  }

  27:                  while (navigator.MoveToNext());

  28:              }

  29:          }

  30:      }

参考书籍

XSLT 2.0 and XPath 2.0 Programmer's Reference (Programmer to Programmer)