C# How can I force Localization Culture to en-US for tests project

Question

How to specify concrente Localization Culture for tests project in C# in VS2008? I'm building Asp .Net MVC app that has nonstandard culture specified in web.config but how to set the same culture for unit tests for that project?

score 75 · Accepted Answer · answered Feb 15 '11 at 08:25

75

You may set

Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US");

in method that is marked as "test initializer" in your unit testing framework.

answered Feb 15 '11 at 08:25

Tony Kh

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you can set this just before the method you are calling that you want to have the specific culture, you don't need to do it in the test setup. and you may not want to if you just need to set it for one test. – Sam Holder Oct 29 '12 at 15:56
3

I'm really wary about challenging such an upvoted answer, but I believe it should be `Thread.CurrentThread.CurrentUICulture` and not CurrentCulture. The Intellisense for CurrentUICulture itself says `Gets or sets the current culture used by the Resource Manager to look up culture-specific resources at run time.` My tests fail when using testing against an "fr-FR" culture resource using CurrentCulture, but pass when using CurrentUICulture. – Neil Moss Sep 21 '15 at 21:25
web.config allows to specify both cultures via . Depending on what attribute you use in the real application you may set the appropriate property for unit test. The original questions asks about culture, not uiCulture but this is subject for interpretation. – Tony Kh Oct 05 '15 at 09:23
I've tested this on VS2015 and it's definitely CultureInfo @NeilMoss – Quango Sep 23 '16 at 08:49
@quango My concern wasn't the `CultureInfo` reference - I was questioning if it should be `CurrentUICulture` instead of `CurrentCulture` – Neil Moss Sep 23 '16 at 12:19
@NeilMoss As you pointed out, `CurrentUICulture` sets the culture used when loading resources. `CurrentCulture` is used for things like converting `DateTime` and `Decimal` values to strings, so chances are, you want both. In your case, it looks like you're using it to test that the correct localized resource strings are returned. In the OP's case, they are probably using it to test how `Decimal` and `DateTime` values are displayed. (They definitely should have specified this in their question.) – Jon Senchyna Aug 30 '17 at 13:35
I'm using MSTEST. What if you want to test multiple cultures, how would I set that up? I don't want to duplicate tests just to run it in a different culture and I don't want to manually change culture settings. It'd be nice to be fully automated. – Rod Nov 22 '21 at 15:34

score 28 · Answer 2 · answered Mar 18 '17 at 22:18

28

If you're using xUnit, you can add the UseCultureAttribute to your project, as defined here:

https://github.com/xunit/samples.xunit/blob/master/UseCulture/UseCultureAttribute.cs

To use it:

[Fact]
[UseCulture("en-US")]
public void MyTest()
{
    // ...
}

answered Mar 18 '17 at 22:18

Drew Noakes

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Was a bit confused by the comment, but when you mean add `UseCultureAttribute` you mean to copy the whole file into your project? Since it seems it is not included in the core nuget https://github.com/xunit/xunit/issues/290 and will never be. – ahong Jan 03 '21 at 06:53
3

@ahong yes, you need to copy that attribute's source code. It's an example of `BeforeAfterTestAttribute` which is part of xUnit. – Drew Noakes Jan 03 '21 at 09:23
For Nuint, its SetCulture – matt Dec 20 '21 at 06:01

Jon Senchyna · Answer 3 · 2020-04-07T17:48:18.977

If you want to specify the CultureInfo for your entire Test Suite without having to add it in the TestInitializer of every TestClass, you can use the AssemblyInitializeAttribute.

Inside a Test Class (a class decorated with the attribute [TestClass]), add a static method that sets DefaultThreadCurrentCulture and DefaultThreadCurrentUICulture, and then decorate that method with [AssemblyInitialize].

This method will then be run once when your test suite starts up, before any TestMethods are run. (Note: you may only have one such method decorated with this attribute in your test suite.)

Here is an example of using a dedicated Test Class that just sets up the culture, but you can put it in any Test Class:

[TestClass]
public static class InitializeCulture
{
    [AssemblyInitialize]
    public static void SetEnglishCultureOnAllUnitTest(TestContext context)
    {
        Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US");
        Thread.CurrentThread.CurrentUICulture = new CultureInfo("en-US");
    }
}

Good approach, but be careful when having multiple threads. The assembly init occurs once, and other threads may be initialized differently. Using the nunit or xUnit attributes for culture is more resilient and self documenting (and can be applied to an entire class). — Abel, Oct 10 '20 at 14:01

score 7 · Answer 4 · answered Feb 26 '19 at 13:55

7

For nUnit 3, you can use the attribute [SetUICulture("en-us")]. This will force the culture for this single test.

answered Feb 26 '19 at 13:55

Klayton Cavalcante

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And putting this before your test class will apply to all your test – m.nachury Mar 12 '19 at 17:52

score 3 · Answer 5 · answered Feb 15 '11 at 11:08

3

System.Globalization.CultureInfo ci = new System.Globalization.CultureInfo("en-US");
System.Threading.Thread.CurrentThread.CurrentCulture = ci;

answered Feb 15 '11 at 11:08

Tausif Baber

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score 1 · Answer 6 · answered Mar 15 '21 at 13:30

The following method worked for me:

[TestClass]
public class MyTestClass
{ 
   [TestInitialize]
   public void InitializeTestClass()
   {
      Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US");
      Thread.CurrentThread.CurrentUICulture = new CultureInfo("en-US");
   }

   .......... [other unit tests]
}

score 0 · Answer 7 · answered Apr 01 '11 at 22:27

There isn't a setting similar to the one in web.config that will work in your case.

You could try setting it for each thread as suggested by the other answers here.

Alternatively if you are using resources created in VS.NET, the code generation creates a static property on the Resource class called 'Culture'. You could set that in your unit test's Suite startup method. That will apply to all the tests that you run.

C# How can I force Localization Culture to en-US for tests project

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