What is unit test in testing?

Question

explain in simpler terms

C# Corner Support · Answer

In .NET technology a unit test is a way to check if an individual piece of code typically a method or function is working correctly. It's like testing a specific ingredient in a recipe to make sure it tastes right before cooking the whole dish. Imagine you have a function in your .NET application that calculates the total price of items in a shopping cart. To create a unit test for this function you would provide it with sample input such as a list of items with known prices and then check if the function correctly calculates the total price. Here's a simplified example in C#: public class ShoppingCart { public decimal CalculateTotalPrice(List itemPrices) { decimal totalPrice = 0; foreach (var price in itemPrices) { totalPrice += price; } return totalPrice; } } And the corresponding unit test using a testing framework like MSTest: [TestClass] public class ShoppingCartTests { [TestMethod] public void CalculateTotalPrice_ShouldReturnCorrectTotal() { // Arrange var shoppingCart = new ShoppingCart(); var itemPrices = new List { 10.50m 20.25m 5.75m }; // Act var total = shoppingCart.CalculateTotalPrice(itemPrices); // Assert Assert.AreEqual(36.50m total); } } In this example the unit test checks if the `CalculateTotalPrice` method in the `ShoppingCart` class correctly calculates the total price based on the provided item prices. If the test passes it indicates that this specific piece of code is functioning as expected. This process helps ensure that each part of your code works independently before integrating it into the larger application ultimately leading to more robust and reliable software.