Question

This is not a homework; I need this for my unit tests.

Sample input: <rows><row><a>1234</a><b>Hello</b>...</row><row>...</rows>.

Sample output: <rows><row><a>0.0</a><b>0.0</b>...</row><row>...</rows>.

You may assume that the document starts with <rows> and that parent node has children named <row>. You do not know the name of nodes a, b, etc.

For extra credit: how to make this work with an arbitrary well-formed, “free-form” XML?

I have tried this with a regex 🙂 without luck. I could make it “non-greedy on the right”, but not on the left. Thanks for your help.

EDIT: Here is what I tried:

    private static string ReplaceValuesWithZeroes(string gridXml)
    {
        Assert.IsTrue(gridXml.StartsWith("<row>"), "Xml representation must start with '<row>'.");
        Assert.IsTrue(gridXml.EndsWith("</row>"), "Xml representation must end with '<row>'.");

        gridXml = "<deleteme>" + gridXml.Trim() + "</deleteme>"; // Fake parent.
        var xmlDoc = XDocument.Parse(gridXml);
        var descendants = xmlDoc.Root.Descendants("row");
        int rowCount = descendants.Count();
        for (int rowNumber = 0; rowNumber < rowCount; rowNumber++)
        {
            var row = descendants.ElementAt(0);
            Assert.AreEqual<string>(row.Value /* Does not work */, String.Empty, "There should be nothing between <row> and </row>!");
            Assert.AreEqual<string>(row.Name.ToString(), "row");

            var rowChildren = row.Descendants();
            foreach (var child in rowChildren)
            {
                child.Value = "0.0"; // Does not work.
            }
        }

        // Not the most efficient but still fast enough.
        return xmlDoc.ToString().Replace("<deleteme>", String.Empty).Replace("</deleteme>", String.Empty);
    }

Answer 1

        XmlDocument doc = new XmlDocument();
        doc.LoadXml(xml);
        foreach (XmlElement el in doc.SelectNodes("//*[not(*)]"))
            el.InnerText = "0.0";
        xml = doc.OuterXml;

or to be more selective about non-empty text nodes:

        foreach (XmlText el in doc.SelectNodes("//text()[.!='']"))
            el.InnerText = "0.0";