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c#.netxmlreaderxmlwriterxmltextreader

What's the path to the document cursor?

I'm using System.Xml.XmlTextReader the forward-only reader. When debugging, at any time I can check the properties LineNumber and LinePosition to see the line number and column number of the cursor. Is there any way I can see any kind of "path" to the cursor with in the document?

For example, in the following HTML document, if the cursor were at *, then the path would be something like html/body/p. I'd find something like this really helpful.

<html>
    <head>
    </head>
    <body>
        <p>*</p>
    </body>
</html>

Edit: I'd also like to be able to inspect XmlWriter similarly.

Solution

  • As far as I know you can't do that with a plain XmlTextReader; you may, however, extend it to provide this feature by way of a new Path property:

    public class XmlTextReaderWithPath : XmlTextReader
{
    private readonly Stack<string> _path = new Stack<string>();

    public string Path
    {
        get { return String.Join("/", _path.Reverse()); }
    }

    public XmlTextReaderWithPath(TextReader input)
        : base(input)
    {
    }

    // TODO: Implement the other constuctors as needed

    public override bool Read()
    {
        if (base.Read())
        {
            switch (NodeType)
            {
                case XmlNodeType.Element:
                    _path.Push(LocalName);
                    break;

                case XmlNodeType.EndElement:
                    _path.Pop();
                    break;

                default:
                    // TODO: Handle other types of nodes, if needed
                    break;
            }

            return true;
        }

        return false;
    }
}