How are test scenarios launched in a project?

In C# projects, frameworks such as NUnit or MSTest are typically used to run test scenarios. Tests are written as methods with attributes, for example [Test] for NUnit. Tests can be run through Visual Studio Test Explorer or via the command line using dotnet test.

Example of a simple test with NUnit:

using NUnit.Framework;

[TestFixture]
public class CalculatorTests
{
    [Test]
    public void Add_TwoNumbers_ReturnsSum()
    {
        var calc = new Calculator();
        Assert.AreEqual(5, calc.Add(2, 3));
    }
}

Thus, tests are run automatically, and results are displayed in a convenient format.