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copied!<p>LINQ to XML is indeed the way here:</p> <pre><code>var textArray = topElement.Elements("L") .Select(x => x.Value) .ToArray(); var text = string.Join(" ", textArray); </code></pre> <p>EDIT: Based on the comment, it looks like you just need a single-expression way of representing this. That's easy, if somewhat ugly:</p> <pre><code>result = (from indexentry in source.Elements(entryLevel) select new IndexEntry { EtiologyCode = indexentry.Element("IE") == null ? null : indexentry.Element("IE").Value, //some code to set other properties in this object Note = string.Join(" ", indexentry.Elements("NO") .Descendants() .Select(x => x.Value) .ToArray()) }; </code></pre> <p>Another alternative is to extract it into a separate extension method (it has to be in a top-level static class):</p> <pre><code>public static string ConcatenateTextNodes( this IEnumerable<XElement> elements) { string[] values = elements.Select(x => x.Value).ToArray(); // You could parameterise the delimiter here if you wanted return string.Join(" ", values); } </code></pre> <p>then change your code to:</p> <pre><code>result = (from indexentry in source.Elements(entryLevel) select new IndexEntry { EtiologyCode = indexentry.Element("IE") == null ? null : indexentry.Element("IE").Value, //some code to set other properties in this object Note = indexentry.Elements("NO") .Descendants() .ConcatenateTextNodes() } </code></pre> <p><strong>EDIT: A note about efficiency</strong></p> <p>Other answers have suggested using <code>StringBuilder</code> in the name of efficiency. I would check for evidence of this being the right way to go before using it. If you think about it, <code>StringBuilder</code> and <code>ToArray</code> do similar things - they create a buffer bigger than they need to, add data to it, resize it when necessary, and come out with a result at the end. The hope is that you won't need to resize too often.</p> <p>The <em>difference</em> between <code>StringBuilder</code> and <code>ToArray</code> here is what's being buffered - in <code>StringBuilder</code> it's the entire contents of the string you've built up so far. With <code>ToArray</code> it's <em>just</em> references. In other words, resizing the internal buffer used for <code>ToArray</code> is likely to be cheaper than resizing the one for <code>StringBuilder</code>, <em>particularly</em> if the individual strings are long.</p> <p>After doing the buffering in <code>ToArray</code>, <code>string.Join</code> is hugely efficient: it can look through <em>all</em> the strings to start with, work out <em>exactly</em> how much space to allocate, and then concatenate it without ever having to copy the actual character data.</p> <p>This is in <a href="https://stackoverflow.com/questions/585860/string-join-vs-stringbuilder-which-is-faster/585897#585897">sharp contrast to a previous answer I've given</a> - but unfortunately I don't think I ever wrote up the benchmark.</p> <p>I certainly wouldn't expect <code>ToArray</code> to be significantly slower, and I think it makes the code simpler here - no need to use side-effects etc, aggregation etc.</p>

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