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Editorial Team
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Asked: 2026-06-14T13:07:59+00:00

I have something similar to the XML below. I’m parsing it using Linq in

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I have something similar to the XML below. I’m parsing it using Linq in C#, and it works great, until we get to a product which doesn’t have a type.

<productList>
    <product>
        <type>
            <colour>red</colour>
        </type>
        <name>First</name>
    </product>
    <product>
        <name>Second</name>
    </product>
</productList>

I’m trying to access the colour element under type, but when the code reaches a product which doesn’t have the type element, I get the “Object reference not set to an instance of an object” error.

Here’s the code I’m using to access it at the moment. Things have got a little complicated with the attempts I’ve tried to solve this.

productColour = products.Element("type").Descendants().FirstOrDefault() == null ? string.Empty : products.Element("type").Descendants().FirstOrDefault().Value,

I know the colour element is always the first underneath type, so I can use .FirstOrDefault(), but I still get the same error using this code.

Can anyone point me towards the right direction? I’ve also tried casting to a string, and also having: ?? " " at the end, all to no avail so far.

Edit: Thanks to @anthony-pegram, it looks like the issue is that I’m always trying to grab the descendants, even if the parent element doesn’t exist. So it looks like I need to check the parent element before grabbing the child – can anyone point me in a direction for this?

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1 Answer

  1. Editorial Team

    Elements() wiil return an IEnumerable. If the element does not exist, IEnumerable will just be empty and calling Elements again on it will not product a null reference exception. The code below should pull the colour from under a product\type element without throwing a null reference exception. If colour or type do not exist, it will return a null.

    (string)product.Elements("type").Elements("colour").FirstOrDefault()
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