How do you use a SortedList<T> to store items in a specific order in C#?

Short answer: Actually, SortedList<TKey, TValue> stores key-value pairs sorted by keys. To store items in a specific order, use the key to represent the sorting criteria. Keys must be unique and implement IComparable or provide a custom IComparer.

Example code

SortedList<int, string> sortedList = new SortedList<int, string>(); sortedList.Add(10, "Ten"); sortedList.Add(5, "Five"); sortedList.Add(20, "Twenty"); // Items automatically sorted by keys: 5, 10, 20 If you want to sort by custom criteria, implement an IComparer and pass it to the SortedList constructor.

Real-world example (ShopNest)

In ShopNest, an order page loads products with List<Product> so you can Add items to the cart and access them by index. Use IEnumerable<T> when you only need to loop (for example, printing invoice lines).

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.