SetCulture

SetCultureAttribute is used to set the current CultureInfo.CurrentCulture for the duration of a test. The culture remains set until the test or fixture completes and is then reset to its original value.

This attribute affects formatting operations such as number formatting, date formatting, and string comparisons that depend on culture settings.

Constructor

SetCultureAttribute(string culture)
Parameter Type Description
culture string The name of the culture to use (e.g., "fr-FR", "de-DE", "en-US"). Must be a valid culture name recognized by CultureInfo.

Applies To

Test Methods Test Fixtures (Classes) Assembly
✅ ✅ ✅
Note

If SetCultureAttribute is applied at fixture or assembly level, the culture setting applies to all contained tests.

When applied at multiple levels, the most specific level takes precedence. The attribute is inherited by derived test fixtures.

Examples

Setting Culture on a Fixture

[TestFixture]
[SetCulture("fr-FR")]
public class FrenchCultureTests
{
    [Test]
    public void TestDateFormatting()
    {
        // This test runs with French culture
        var date = new DateTime(2024, 12, 25);
        string formatted = date.ToString("d");

        // French date format: dd/MM/yyyy
        Assert.That(CultureInfo.CurrentCulture.Name, Is.EqualTo("fr-FR"));
    }

    [Test]
    public void TestNumberFormatting()
    {
        // French uses comma as decimal separator
        double value = 1234.56;
        string formatted = value.ToString("N2");

        Assert.That(formatted, Does.Contain(","));
    }
}

Setting Culture on Individual Methods

[TestFixture]
public class MixedCultureTests
{
    [Test]
    [SetCulture("de-DE")]
    public void TestWithGermanCulture()
    {
        // Only this test runs with German culture
        Assert.That(CultureInfo.CurrentCulture.Name, Is.EqualTo("de-DE"));
    }

    [Test]
    [SetCulture("ja-JP")]
    public void TestWithJapaneseCulture()
    {
        // Only this test runs with Japanese culture
        Assert.That(CultureInfo.CurrentCulture.Name, Is.EqualTo("ja-JP"));
    }

    [Test]
    public void TestWithDefaultCulture()
    {
        // This test runs with the system's default culture
        Assert.That(CultureInfo.CurrentCulture, Is.Not.Null);
    }
}

Combining with SetUICulture

[TestFixture]
public class CombinedCultureTests
{
    [Test]
    [SetCulture("fr-FR")]
    [SetUICulture("de-DE")]
    public void TestWithDifferentCultures()
    {
        // Culture affects formatting (numbers, dates)
        Assert.That(CultureInfo.CurrentCulture.Name, Is.EqualTo("fr-FR"));

        // UICulture affects resource loading (UI strings)
        Assert.That(CultureInfo.CurrentUICulture.Name, Is.EqualTo("de-DE"));
    }
}

Notes

  1. Only one culture may be specified per attribute. To test with multiple cultures, create separate test methods or use parameterized tests.
  2. SetCulture affects CultureInfo.CurrentCulture, which controls formatting operations. Use SetUICulture to control CultureInfo.CurrentUICulture for resource loading.
  3. If you need to conditionally run tests based on the current culture (rather than setting it), use the Culture attribute instead.

See Also