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C# Generic List.Any() throws System.NullReferenceException

Consider the following partial view code snippet

List<sellingPrice> Prices = ViewBag.Prices;
foreach (var mgmp in mg.messageGroup.messageGroupMessagePLUs)
{
    if (Prices.Any(x => x.pluId == mgmp.messagePLU.plu.pluId))
    {
        //do stuff
    }
}

For specific products in the db, the line

if (Prices.Any(x => x.pluId == mgmp.messagePLU.plu.pluId))

throws a System.NullReferenceException. Inspecting the code shows that mgmp is an object and Prices contains elements. However, the value of x is null. Now, I am under the impression that I am simply testing whether or not any "x" exists that satisfies my test, not asking it to return an "x".

It's a very irritating problem. Hopefully someone can point out the really obvious solution.

like image 328
Captain Kenpachi Avatar asked Jan 16 '13 15:01

Captain Kenpachi


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2 Answers

Try:

Prices.Any(x => x!=null && x.pluId == mgmp.messagePLU.plu.pluId)

You might need to do other null checks if for example .messagePLU can be null

like image 101
Johan Larsson Avatar answered Sep 25 '22 02:09

Johan Larsson


The most likely reason why this happens is because one or more items in the ViewBag.Prices is null. Check x for null, or see why prices contain nulls in the first place, assuming it's not supposed to have any null values.

like image 28
Sergey Kalinichenko Avatar answered Sep 26 '22 02:09

Sergey Kalinichenko