Dec 30, 2010 · The HashSet class in C# goes for the first approach, thus not preserving the order of elements. It is much faster than a regular List. Some basic benchmarks showed that HashSet is decently faster when dealing with primary types (int, double, bool, etc.). It is a lot faster when working with class objects. So the point is that HashSet is fast.

May 29, 2016 · HashSet is a class derived from Set interface. As a derived class of Set, the HashSet attains the properties of Set. Important and the most frequently used derived classes of Set are HashSet and TreeSet.

Mar 21, 2024 · 1) First and most significant difference between HashMap and HashSet is that HashMap is an implementation of Map interface while HashSet is an implementation of Set interface, which means HashMap is a key value based data-structure and HashSet guarantees uniqueness by not allowing duplicates.In reality HashSet is a wrapper around HashMap in ...

Jan 11, 2010 · Set<String> s = new HashSet<String>() {{ add("a"); add("b"); }} Keep in mind that this will actually create an new subclass of HashSet each time it is used, even though one does not have to explicitly write a new subclass. A utility method

Aug 18, 2012 · Consider my HashSet containing a list of MyHashObjects with their hashCode() and equals() methods overridden correctly. I was hoping to construct a MyHashObject myself, and set the relevant hash code properties to certain values. I can query the HashSet to see if there "equivalent" objects in the set using the contains() method.

Jan 18, 2015 · Don't use FirstOrDefault; just use HashSet.Contains(p) and HashSet.Remove(p) where 'p' is a new instance of CachedPath with the properties that you are looking for. I ran into exactly the same question, which is why I ran into this post. My case was similar to your case, where the items stored needed to be looked up by several properties ...

It's clear that a search performance of the generic HashSet&lt;T&gt; class is higher than of the generic List&lt;T&gt; class. Just compare the hash-based key with the linear approach in the List&lt...

Jan 21, 2012 · HashSet<T> constructor receive object what implement IEqualityComparer<T> for adding new object. If you want to use method in HashSet you need to overrride Equals() and GetHashCode() .

public static class Extensions { public static HashSet<T> ToHashSet<T>( this IEnumerable<T> source, IEqualityComparer<T> comparer = null) { return new HashSet<T>(source, comparer); } } Note that you really do want an extension method (or at least a generic method of some form) here, because you may not be able to express the type of T explicitly:

Sep 28, 2016 · I have the following class. class Test{ public HashSet<string> Data = new HashSet<string>(); } I need to change the field "Data" from different threads, so I would like some opinions on my current thread-safe implementation.