Assert.That(myTestDelegate, Throws.ArgumentException
    .With.Property("Message").EqualTo("your argument is invalid."));

您现在可以使用ExpectedException属性，例如:

[Test]
[ExpectedException(typeof(InvalidOperationException), 
 ExpectedMessage="You can't do that!"]
public void MethodA_WithNull_ThrowsInvalidOperationException()
{
    MethodA(null);
}

由于我被一些新的NUnit模式的冗长所困扰，我使用这样的方法来创建对我个人来说更清晰的代码:

public void AssertBusinessRuleException(TestDelegate code, string expectedMessage)
{
    var ex = Assert.Throws<BusinessRuleException>(code);
    Assert.AreEqual(ex.Message, expectedMessage);
}

public void AssertException<T>(TestDelegate code, string expectedMessage) where T:Exception
{
    var ex = Assert.Throws<T>(code);
    Assert.AreEqual(ex.Message, expectedMessage);
}

用法是:

AssertBusinessRuleException(() => user.MakeUserActive(), "Actual exception message");

断言例外:

Junit 5:

    @Test
    public void whenExceptionThrown_thenAssertionSucceeds() {
        Exception exception = assertThrows(NumberFormatException.class, () -> {
            Integer.parseInt("1a");
        });
    
        String expectedMessage = "For input string";
        String actualMessage = exception.getMessage();
    
        assertTrue(actualMessage.contains(expectedMessage));
    }

在Junit 4中:

@Test(expected = NullPointerException.class)
public void whenExceptionThrown_thenExpectationSatisfied() {
    String test = null;
    test.length();
}

要扩展persistent的答案，并提供更多的NUnit功能，你可以这样做:

public bool AssertThrows<TException>(
    Action action,
    Func<TException, bool> exceptionCondition = null)
    where TException : Exception
{
    try
    {
        action();
    }
    catch (TException ex)
    {
        if (exceptionCondition != null)
        {
            return exceptionCondition(ex);
        }
        return true;
    }
    catch
    {
        return false;
    }

    return false;
}

例子:

// No exception thrown - test fails.
Assert.IsTrue(
    AssertThrows<InvalidOperationException>(
        () => {}));

// Wrong exception thrown - test fails.
Assert.IsTrue(
    AssertThrows<InvalidOperationException>(
        () => { throw new ApplicationException(); }));

// Correct exception thrown - test passes.
Assert.IsTrue(
    AssertThrows<InvalidOperationException>(
        () => { throw new InvalidOperationException(); }));

// Correct exception thrown, but wrong message - test fails.
Assert.IsTrue(
    AssertThrows<InvalidOperationException>(
        () => { throw new InvalidOperationException("ABCD"); },
        ex => ex.Message == "1234"));

// Correct exception thrown, with correct message - test passes.
Assert.IsTrue(
    AssertThrows<InvalidOperationException>(
        () => { throw new InvalidOperationException("1234"); },
        ex => ex.Message == "1234"));

一个真正有效的解决方案:

public void Test() {
    throw new MyCustomException("You can't do that!");
}

[TestMethod]
public void ThisWillPassIfExceptionThrown()
{
    var exception = Assert.ThrowsException<MyCustomException>(
        () => Test(),
        "This should have thrown!");
    Assert.AreEqual("You can't do that!", exception.Message);
}

这可以使用Microsoft.VisualStudio.TestTools.UnitTesting;。