Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

C# C# Collections Sets and Dictionaries HashSet

Posted by chazber
chazber
4,873 Points

How exactly does the HashSet class prevent duplicate items in its collection?

?

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

The HashSet relies on an equality comparison method, either one associated with the type by default or one explicitly provided during instantiation, to insure that each added element is unique.

For more details, see the documentation page on HashSet.