Question

How can I use a XML file as a database and execute some basic SELECT command only on it !
ex: select author from file.xml where title=”MyTitle”

<?xml version="1.0"?>
<catalog>
<book id="bk101">
  <author>Gambardella, Matthew</author>
  <title>XML Developer's Guide</title>
</book>
<book id="bk102">
  <author>Ralls, Kim</author>
  <title>Midnight Rain</title>
</book>
</catalog>

I’ve never worked with XML file (as DB) so have no code to put here, but hope someone have some solution !

Answer 1

You can look into XPath. The System.XML.XmlDocument.SelectNodes method allows you to select matching nodes via XPath. It’s not SQL, but it’s a common way to find nodes in an XML document. The following example uses XPath to retrieve the authors of all the books with a title of “Midnight Rain”.

    Dim document As XmlDocument = New XmlDocument()
    document.Load("file.xml")
    Dim matches As XmlNodeList = document.SelectNodes("/catalog/book[title = 'Midnight Rain']/author")
    For Each node As XmlNode In matches
        'Do work
    Next