Editing NUnit (section)

== Example ==
Example of an NUnit [[test fixture#Test fixture in xUnit|test fixture]]:{{citation needed|date=January 2017}}
<syntaxhighlight lang="csharp">
using NUnit.Framework;
 
[TestFixture]
public class ExampleTestOfNUnit
{
    [Test]
    public void TestMultiplication()
    {
        Assert.AreEqual(4, 2*2, "Multiplication");
        
        // Equivalently, since version 2.4 NUnit offers a new and
        // more intuitive assertion syntax based on constraint objects
        // [http://www.nunit.org/index.php?p=constraintModel&r=2.4.7]:
        Assert.That(2*2, Is.EqualTo(4), "Multiplication constraint-based");
    }
}

// The following example shows different ways of writing the same exception test.

[TestFixture]
public class AssertThrowsTests
{
    [Test]
    public void Tests()
    {
        // .NET 1.x
        Assert.Throws(typeof(ArgumentException),
            new TestDelegate(MethodThatThrows));
	    
        // .NET 2.0
        Assert.Throws<ArgumentException>(MethodThatThrows);
        Assert.Throws<ArgumentException>(
	    delegate { throw new ArgumentException(); });

        // Using C# 3.0	    
        Assert.Throws<ArgumentException>(
            () => { throw new ArgumentException(); });
    }
    
    void MethodThatThrows()
    {
        throw new ArgumentException();
    }
}

// This example shows use of the return value to perform additional verification of the exception.

[TestFixture]
public class UsingReturnValue
{
    [Test]
    public void TestException()
    {
        MyException ex = Assert.Throws<MyException>(
            delegate { throw new MyException("message", 42); });
        Assert.That(ex.Message, Is.EqualTo("message"));
        Assert.That(ex.MyParam, Is.EqualTo(42)); 
    }
}

// This example does the same thing using the overload that includes a constraint.

[TestFixture]
public class UsingConstraint
{
    [Test]
    public void TestException()
    {
        Assert.Throws(Is.Typeof<MyException>()
                                 .And.Message.EqualTo("message")
                                 .And.Property("MyParam").EqualTo(42),
            delegate { throw new MyException("message", 42); });
    }
}
</syntaxhighlight>

The NUnit framework discovers the method <code>ExampleTestOfNUnit.TestMultiplication()</code> automatically by [[reflection (computer science)|reflection]].{{citation needed|date=January 2017}}