Question

We store static data in an XML file with different groupings of data. The file is actually quite large and I’ve pared it down for this question. Each of these are a small subset of their data.

<?xml version="1.0" encoding="utf-8" ?>
<datasets>
    <dataset id="USRegions">
        <record code="SoCal">Southern California</record>
        <record code="NoCal">Northen California</record>
    </dataset>
    <dataset id="Countries">
        <record code="US" callingcode="1|US">United States</record>
        <record code="CA" callingcode="1|CA">Canada</record>
        <record code="GB" callingcode="44|GB">United Kingdom</record>
        <record code="MX" callingcode="52|MX">Mexico</record>
    </dataset>
</datasets>

For purposes of validation I want to make sure that the passed in country code, “US” for example, exists in the static data. I can get to the recordset with this query, but I’m stumped on how to drill deeper into the data.

var dataset = from record in _xAddressData.Descendants("dataset")
          where (string) record.Attribute("id") == "Countries"
          select record.DescendantNodes();

Answer 1

One approach:

static bool HasCountry(this XDocument document, string country)
{
    return document.Root.Elements("dataset")
                        .Any(d => (string)d.Attribute("id") == "Countries"
                          && d.Elements("record")
                              .Any(r => (string)r.Attribute("code") == country));
}

Used like:

var hasUS = _xAddressData.HasCountry("US");