The following table lists the effects of these methods on different node types. Now) Xml Reader Settings settings = new Xml Reader Settings(); settings. Given that the validity of an element is dependent on the validity of its child elements and attributes, modifications to either result in altering the validity of the element if it was previously valid. Xml Document XPath Document XPath Navigator Process XML Data Using the XPath Data Model Insert XML Data using XPath Navigator Remove XML Data using XPath Navigator Note The feedback system for this content will be changing soon. If content within a comment thread is important to you, please save a copy.The XPath Navigator class also provides a set of methods used to insert and remove nodes. Specifically, if the child elements or attributes of an element are inserted, updated, or deleted, then the validity of the element becomes unknown. For more information on the upcoming change, we invite you to read our blog post.
Now); The XPath Navigator class uses the W3C XML Schema as a basis for describing strongly-typed XML. The following example uses the Outer Xml property to modify the value of the Dim document As Xml Document = New Xml Document() document. namespace declaration is automatically inserted by the XPath Navigator class to preserve the consistency of the rest of the XML document. Note When the underlying document is modified, it is advisable to rerun the select. Notice in the previous example that when a node is modified in the selected Xml Node List the underlying document is also modified. Note If the XPath expression does not include a prefix, it is assumed that the namespace Uniform Resource Identifier (URI) is the empty namespace. Add Namespace("bk", "urn:newbooks-schema") ' Select all nodes where the book price is greater than 10.00. Select Nodes( _ "descendant::bk:book[bk:price10.00]", nsmgr) For Each book As Xml Node In node List Dim price As Double price = Math. Notice that the code examples above use the Xml Namespace Manager to resolve the namespace of the document.XPath Navigator objects that can edit an XML document are created by the Create Navigator method of the Xml Document class. has to contain a numeric value between -21474836483647 to be schema-valid. The W3C XML Schema recommendation introduces the concept of an element being nillable.XPath Navigator objects created by the XPath Document class are read-only and any attempt to use the editing methods of an XPath Navigator object created by an XPath Document object result in a Not Supported Exception. Create("contoso Books.xml", settings); Xml Document document = new Xml Document(); document. For complex types, the schema-validity of the element is dependent on the schema-validity of its child elements and attributes. When an element is nillable, it is possible for the element to have no content and still be valid. If the XPath expression includes a prefix, the prefix and namespace URI pair must be added to the Xml Namespace Manager, and the Xml Namespace Manager is passed to the Select Nodes(String, Xml Namespace Manager) or Select Single Node(String, Xml Namespace Manager) method. If the node modified is one that could cause the node to be added to the node list when it was not previously, or would now cause it to be removed from the node list, there is no guarantee that the node list is now accurate. Namespace resolution is supported using the Xml Namespace Manager.The DOM classes provide two methods for XPath selection: the Select Single Node method and the Select Nodes method. Add Namespace("bk", "urn:newbooks-schema") ' Select and display the first node in which the author's ' last name is Kingsolver. Select Single Node( _ "descendant::bk:book[bk:author/bk:last-name=' Kingsolver']", nsmgr) Console. Inner Xml) // Load the document and set the root element. Finally, the updated file is written to the console. For more information on the upcoming change, we invite you to read our blog post.The Select Single Node method returns the first node that matches the selection criteria. The file (which is provided at the end of this topic) is used as the input file.