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C# Querying With LINQ Query Operators Generation Operators

Posted by Jessie Cui
Jessie Cui
7,607 Points

DefaultIfEmpty

Does DefaultIfEmpty only return a one value set of the default value? Or does it also mutate the set it was called on, if it was empty, and change it to a set with one instance of it's default value?

1 Answer

Steven Parker
Steven Parker
229,785 Points
Steven Parker
Steven Parker
229,785 Points

DefaultIfEmpty does not mutate the set it was called on.

If the set is empty, it returns a singleton collection (your "one value set") containing the default value for the type.

For more information, see the MSDN Documenation.