VB.NET XML Parser - Find elements with specific attribute & value

Question

HI,

I am using VB.NET to read an XHTML file. I need my program to find every element within the XML structure which has the "class" attribute set to a specific value.

IE: I need an array (or similar list) of all elements from the document which contain class="mytag".

There is a list of several values I need to detect, all of which start with the same word 'mytag' followed by another word - so using a "contains" function seems sensible here.

Any suggestions of ways I can parse out these attributes would be appreciated. Cheers.

Answer 1

Use the following XPath expression with the SelectNodes function of an XmlDocument object:

//*[@class="mytag"]

This expression will select any XHTML element whose class attribute's value is equal to "mytag".

If you want to find all elements whose class attribute contains a particular string, the XPath function contains will help you:

//*[contains(@class,"mytag")]

The SelectNodes function returns a list of XML nodes from the XmlDocument corresponding on the XPath expression passed to it as a parameter. Based on your description, it's exactly what you need.

Answer 2

If you are OK with LINQ try XML literals,

Like this:

Dim nodes = From currentNode In XmlDoc...<your-node-name>

For Each node As XElement In nodes

Console.Writeline(node.Attribute("attr-name").Value())

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