CODEWITHSUNDEEP
c#.netlinqlinq-to-entities
1011 1110
1011 1110

Reputation: 781

Linq null error

Coding up a statistics page for my website. I am using Linq with entity framework. I have a couple queries that work, but can't handle null exceptions. Just wondering if there is a way around it without having to readjust coding approach.

        var countriesElse = db.Profiles
            .GroupBy(av => av.Country)
            .Select(g => new { Country = g.Key, Count = g.Count() });
        var otherCount = countriesElse
            .Where(x => x.Country != "US" && x.Country != "CA").FirstOrDefault();

        ViewBag.otherCount = otherCount.Count;

This throws a null error because there is nothing to select with this where clause, but I will be needing this query for future purposes because eventually it will be used.

Cheers

Upvotes: 0

Views: 133

Answers (1)

Selman Genç
Selman Genç

Reputation: 101681

Maybe you want something like this:

if(otherCount != null)
   ViewBag.otherCount = otherCount.Count;

else ViewBag.otherCount = 0;

Select or Where will not throw a NullReferenceException if you don't try to access a property or method of null object in the query.Your problem is about the last line.

Also you can simplify your code using FirstOrDefault with a predicate:

 var profile = db.Profiles
        .GroupBy(av => av.Country)
        .Select(g => new { Country = g.Key, Count = g.Count() })
        .FirstOrDefault(x => x.Country != "US" && x.Country != "CA");

ViewBag.otherCount = profile== null ? 0 : profile.Count;

Upvotes: 2

Related Questions