What are the differences between Dictionary and HashSet in C#?

What are the differences between Dictionary and HashSet in C#?

In C#, a Dictionary is a collection of key-value pairs, while a HashSet is a collection of unique values. Would you like to know more about their use cases?

Yes, can you explain when to use each one?

Use a Dictionary when you need to associate values with unique keys, like a phone book. Use a HashSet when you need to ensure all items are unique, like a list of unique user IDs.

Are there any performance differences between them?

Yes, Dictionary generally has faster lookups for key-value pairs, while HashSet is optimized for checking the existence of items.

Can you give me a code example for both?

Sure! For Dictionary: var dict = new Dictionary<string, int>(); dict.Add("apple", 1); For HashSet: var set = new HashSet<string>(); set.Add("apple");.