C# LINQ use xml with case insensitive queries

Question

I was trying to use a LINQ query that will iterate through an xml document. However I wanted to either use an OR statement or a string.toLower() to make sure it will always get the data it needs

I currently have:

// read all <item> tags and put the in an array.
XDocument xml = XDocument.Parse(xmlData);
var newItems = (from story in xml.Descendants("item")
    select new Feed
    {
        Title = ((string) story.Element("title")),
            Link = ((string) story.Element("link")),
            Description = ((string) story.Element("description")),
            PublishDate = ((string) story.Element("pubDate")),
    }
).Take(20).ToList();

what I still want to change:

(E.G.) Title = ((string)story.Element("title")) needs to search case insensitive.
from story in xml.Descendants("item") select new Feed needs to search in item as well as in entry (both case-insensitive).

PS: as I am iterating through the an RSS document I cannot directly access the XML document.

thanks for input.

"`((string)story.Element("title"))` need to search case insansitive" Does this mean you have both `title` and `Title` in your xml? I don´t understand what you mean by search case-insensitive. — MakePeaceGreatAgain, Dec 06 '16 at 15:14
Possible duplicate of [Case insensitive XML parser in c#](http://stackoverflow.com/questions/9334771/case-insensitive-xml-parser-in-c-sharp) — simonalexander2005, Dec 06 '16 at 15:18
@HimBromBeere, that no matter whether its title or TiTle it returns the same result. — Rodney Wormsbecher, Dec 06 '16 at 15:19

score 2 · Accepted Answer · edited Mar 07 '18 at 09:57

You can aways create extension methods for that. Here is the class that I normally use:

public static class XElementExtensions {
    public static bool EqualsIgnoreCase(this XName name1, XName name2) {
        return name1.Namespace == name2.Namespace &&
            name1.LocalName.Equals(name2.LocalName, StringComparison.OrdinalIgnoreCase);
    }

    public static XElement GetChild(this XElement e, XName name) {
        return e.EnumerateChildren(name).FirstOrDefault();
    }

    public static IEnumerable<XElement> EnumerateChildren(this XElement e, XName name) {
        return e.Elements().Where(i = > i.Name.EqualsIgnoreCase(name));
    }
}

Then, you can change your code to something like this:

var newItems = (from story in xml.Root.EnumerateChildren("item")
select new Feed
{
    Title = ((string) story.GetChild("title")),
        Link = ((string) story.GetChild("link")),
        Description = ((string) story.GetChild("description")),
        PublishDate = ((string) story.GetChild("pubDate")),
}).Take(20).ToList();

score 0 · Answer 2 · answered Dec 06 '16 at 15:17

0

XML is typically defined by a schema - it should have a fixed format for the element names - so title isn't the same as TiTlE in XML terms. I don't think it's possible to do what you want, using .Element

answered Dec 06 '16 at 15:17

simonalexander2005

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yes I found that as well however different RSS have different schedules so thought instead of making 3 queries, I'll see whether anyone has ever found a solution to this. – Rodney Wormsbecher Dec 06 '16 at 15:18
There probably are ways to do it - e.g. convert all of the XML tags to upper-case before starting. e.g. http://stackoverflow.com/questions/9334771/case-insensitive-xml-parser-in-c-sharp – simonalexander2005 Dec 06 '16 at 15:25

C# LINQ use xml with case insensitive queries

2 Answers2