[Applied] Build a Simple Inventory Management Tool

In this lesson you will build a simple inventory management program using a Dictionary in C#, putting everything you have learned together. This is for anyone searching for "C# inventory management applied implementation".

Combine the Dictionary and loops you have learned so far into a program that tracks stock levels. A Dictionary looks up and updates values quickly by key, which makes it one of the most heavily used data structures in real applications.

The sample code sets values by key with items["apple"] = 10, reduces stock with items["apple"] -= 3, and lists every product with a foreach loop. Notice how item.Key and item.Value reach the key and the value.

A common stumbling block for beginners is the error you get from reaching for a key that does not exist. Real systems have to cope with products at zero stock or names that were never registered, so checking with ContainsKey() first is an important habit.

In real-world development, managing data by a name or a number as the key - inventory, orders, membership - is the basic shape of a business system, and key/value structures like Dictionary are used widely for it.

📖 Reference code

var items = new Dictionary<string, int>();
items["apple"] = 10;
items["orange"] = 5;
items["apple"] -= 3;
foreach (var item in items) {
    Console.WriteLine($"{item.Key}: {item.Value}");
}

✍️ Your code

Type your code, then press "Run"

🧪 This site can't compile or run C# directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser — nothing is sent anywhere).