XML learning notes (7): XPath data mode

• The XPath data mode depends on the XPathNavigator class stored in the System. Xml. XPath namespace.
• The XPathNavigator class is an abstract class. It is a pointer-based XML data browsing mode that allows you to edit XML files.
• You can obtain an instance of the XPathNavigator class from any class that implements the IXPathNavigable interface. XmlDocument and XPathDocument are the classes that implement this interface.
• The XML returned by XmlDocument is editable, and the returned object of XPathDocument is read-only.

Create an XPathNavigator object:

 

1: // functional sample code:

   2:  private void button1_Click(object sender, EventArgs e)

   3:      {

   4:          XPathNavigator navigator = null;

   5:          if (radioButton1.Checked)

   6:          {

7: // create an XPathNavigator object in the XmlDocument class

   8:              XmlDocument doc = new XmlDocument();

   9:              doc.Load(Application.StartupPath + @"/employees.xml");

  10:              navigator = doc.CreateNavigator();

  11:          }

  12:          else

  13:          {

14: // create an XPathNavigator object in the XmlPathDocument class

  15:              XPathDocument doc = new XPathDocument(Application.StartupPath + @"/employees.xml");

  16:              navigator = doc.CreateNavigator();

  17:          }

  18:          MessageBox.Show("Navigator created successfully!");

  19:      }

Use XPathNavigator to browse XML documents

 

   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:      }

Reference books

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