Enumerable.Empty<T>() equivalent for IQueryable
When a method returns IEnumerable<T> and I do not have anything to return, we can use Enumerable.Empty<T>().
Is there an equivalent to the above for a method returning IQueryable<T>
Maybe:
Enumerable.Empty<T>().AsQueryable();
Enumerable.Empty<T>().AsQueryable(); should do it.
Try return new T[0].AsQueryable();
Say you have an IQueryable<T> called result:
return result.Take(0);
I would advise against alejandrobog's answer as this will still use memory to create an empty array.
Array.Empty<T>().AsQueryable();
or
Enumerable.Empty<T>().AsQueryable();
are preferred. Array.Empty will allocate a static typed array so only one empty array of T is created and that is shared amongst all Empty queryables.
Array.Empty<T> is only available after .NET Framework 4.6. For earlier versions, you can use new object[0].Cast<T>()
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Unionqueries to be broken up into multiple queries instead of one.Union, but probably when you try something after this. This answer is accepted and voted but it can be very misleading. @Sunny Please consider to edit your answer. Answer in this question helped me: Enumerable.Empty<T>().AsQueryable(); This method supports the LINQ to Entities infrastructure and is not intended to be used directly from your code .