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c# - Reading XML using XDocument & Linq - check if element is NULL?

I'm using LINQ together with XDocument to read a XML File. This is the code:

XDocument xml = XDocument.Load(filename);

var q = from b in xml.Descendants("product")
        select new
        {
            name = b.Element("name").Value,
            price = b.Element("price").Value,                    
            extra = b.Element("extra1").Value,
            deeplink = b.Element("deepLink").Value                   
        };

Now the problem is, the extra1 field is not always present. There are items in the XML file without that node. If that happens it's crashing with a NullReferenceException.

Is there any possibility to include a "check if null" so I can prevent it from crashing?

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by (71.8m points)

Use (string) instead of .Value:

var q = from b in xml.Descendants("product")
        select new
        {
            name = (string)b.Element("name"),
            price = (double?)b.Element("price"),                    
            extra = (string)b.Element("extra1"),
            deeplink = (string)b.Element("deepLink")                   
        };

This also works with other datatypes, including many nullable types in case the element is not always present.


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