Is there a one liner to verify XML string structure?

Question

I have a string:

Dim strXMLTags As String = "<tags><test>1</test></tags>"

And I want to verify that all opening tags have a closing tag in the proper place. So if I put the previous string through, it'd work. However, if I put:

Dim strXMLTags As String = "<tags><test>1</test>"

Then I want it to give me an error. Is there an XML structure checker or something of the sorts? Or should I just try and load it to an XML document and if it errors then, then I know. Thanks.

Answer 1

The easiest way would indeed be to try loading it into an xml document, and see if it crashes or not.

Answer 2

Well I wouldn't know of a one-liner, but there are ways to check for valid XML:

1. XSDs
2. HTML Tidy
3. Creating a temporary XML file and checking it's validity

1: XSDs - no need to explain here. When you have a correct schema for your XML you can validate against an XSD and see errors right away, this way you would even find missings tags etc.

2: HTMLTidy is the best resource for cleaning up messy HTML code. I am sure you could create something to only check your code. Check the HTMLTidy SourceForge page and a Tidy .NET Implementation here.

3: Temp XML - (my personal favorite) just create a new XmlTextReader and after writing your XML somewhere temporary read it in again and check for errors. There is some sample code on this page, it uses a ValidationSchema though which you might not have? Actually there is are some posts about XML Validation in VB.Net on that page.