Use XPath to query XML data (VB.net) : XPath « XML « ASP.NET Tutorial
- ASP.NET Tutorial
- XML
- XPath
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Xml" %>
<%@ Import Namespace="System.Xml.XPath" %>
<script runat="server">
sub SelectData(Sender as Object, e as EventArgs)
Dim objReader as New XmlTextReader(Server.MapPath("Data.xml"))
Dim objDoc as XPathDocument = new XPathDocument(objReader)
Dim objNav as XPathNavigator = objDoc.CreateNavigator()
try
Dim expr as XPathExpression = objNav.Compile(tbQuery.Text)
Dim mngr as XmlNamespaceManager = new XmlNamespaceManager(objReader.NameTable)
mngr.AddNamespace("","x-schema:books.xdr")
expr.SetContext(mngr)
dim objIterator as XPathNodeIterator = objNav.Select(expr)
While objIterator.MoveNext()
Format(objIterator.Current)
end while
catch ex As Exception
Response.Write(ex.Message)
end try
objReader.Close()
end sub
Private Sub Format(objNav As XPathNavigator)
Dim strValue As String
Dim strName As String
If objNav.HasChildren then
strName = objNav.Name
objNav.MoveToFirstChild()
strValue = objNav.Value
Else
strValue = objNav.Value
strName = objNav.Name
End If
Response.Write("<<b>" & strName & _
"</b>>" & strValue & "<br>")
End Sub
</script>
<html><body>
<form runat=server>
<asp:Textbox id="tbQuery" runat=server/>
<asp:Button id="btnSubmit" text="Submit"
runat=server OnClick="SelectData"/><BR>
</form>
</body></html>
File: Data.xml
<?xml version="1.0"?>
<bookstore>
<book genre="asdf">
<title>asdf</title>
<author>
<first-name>asdf</first-name>
<last-name>asdf</last-name>
</author>
<price>asdf</price>
</book>
<book genre="asdf">
<title>asdf</title>
<author>
<first-name>asdf</first-name>
<last-name>asdf</last-name>
</author>
<price>asdf</price>
</book>
<book genre="asdf">
<title>asdf</title>
<author>
<first-name>asdf</first-name>
<last-name>asdf</last-name>
</author>
<price>asdf</price>
</book>
</bookstore>