Localization

  • 5 minutes to read

Localization set-up consists of the following parts:

  • Localize date, number, and currency values. There are two methods to do this:

  • Localize messages. To do this, use dictionaries that contain localized messages for different languages. The DevExtreme distribution includes predefined dictionaries (the dx.messages.[lang].js files in your project's wwwroot/js/devextreme/localization directory). Use these files as is or as a base for a custom dictionary.

  • Set the locale.

This document contains step-by-step instructions for the Intl and Globalize methods.

Intl

To set up localization based on the Intl object, follow the steps below.

Step 1. Reference Dictionaries

Open the file where DevExtreme scripts are referenced (for example, the _Layout.cshtml file) and reference dictionaries before the closing head tag:

<head>
...
    @* reference dictionaries *@
    <script src="~/js/devextreme/localization/dx.messages.de.js"></script>
    <script src="~/js/devextreme/localization/dx.messages.es.js"></script>
</head>

Step 2. Set the Locale

You should set the locale to apply string translation and data formatting. To do this, add the script block to Razor files where you configure DevExtreme-based controls or to the project's layout that applies to all pages in the application and call the DevExpress.localization.locale method. For example, the following code sets German as the default locale:

<script>
    DevExpress.localization.locale("de");
</script>

You can also set the locale based on the client locale or dynamically (for example, your application contains a control that allows to switch a language, and the locale can depend on the selected language).

NOTE

Demo: Using Intl

Globalize

Follow the steps below to set up localization based on the Globalize library.

Ensure the Globalize modules and CLDR scripts are linked in the _Layout.cshtml/_DevExtreme_Layout.cshtml or bundleconfig.json file.

<head>
    //...
    <script src="~/js/devextreme/cldr.js"></script>
    <script src="~/js/devextreme/cldr/event.js"></script>
    <script src="~/js/devextreme/cldr/supplemental.js"></script>
    <script src="~/js/devextreme/cldr/unresolved.js"></script>

    <script src="~/js/devextreme/globalize.js"></script>
    <script src="~/js/devextreme/globalize/message.js"></script>
    <script src="~/js/devextreme/globalize/number.js"></script>
    <script src="~/js/devextreme/globalize/currency.js"></script>
    <script src="~/js/devextreme/globalize/date.js"></script>
    //...
</head>

These files are added and linked in the project in the following cases:

The corresponding code lines are commented out, you need to uncomment them.

Step 2. Obtain CLDR Data Files

The Globalize library requires CLDR data files. To get and add these files to the project:

  1. Ensure Node.js is installed on your computer.

  2. Create a temp directory anywhere on your computer.

  3. Open the console from this directory and run the following commands:

    npm init -y
    npm i cldr-data
    

    You can find the downloaded CLDR JSON files in <temp_directory>/node_modules/cldr-data.

  4. Copy the cldr-data directory to the <your_project>/wwwroot directory.

NOTE

The cldr-data directory contains data for a large number of languages. To reduce the directory's size, you can remove unnecessary languages data from the cldr-data/main subdirectory.

Step 3. Add Code that Loads CLDR Data for Required Cultures and Sets the Default Locale

To load CLDR JSON files, open your controller's code and create an action method that uses the CldrDataScriptBuilder helper.

IMPORTANT

If you use Razor Pages, you should first create a controller.

The code below demonstrates a Home controller with a CldrData action. This action loads CLDR JSONs for German and Spanish locales from the node_modules/cldr-data directory and sets German as the default locale:

public class HomeController : Controller {
    public IActionResult Index() {
        return View();
    }

    public ActionResult CldrData() {
        return new DevExtreme.AspNet.Mvc.CldrDataScriptBuilder()
            .SetCldrPath("~/wwwroot/cldr-data")
            .SetInitialLocale("de")
            .UseLocales("de", "es")
            .Build();
    }
}

You can also set the locale based on the client locale or dynamically (for example, your application contains a control that allows to switch a language, and the locale can depend on the selected language).

Step 4. Reference Dictionaries and Load CLDR Data

  1. Open the file where DevExtreme scripts are referenced. Typically, it is the _Layout.cshtml file.

  2. Before the closing head tag:

    • Add a script element that loads CLDR data from the CldrData action method. To do this, use the @Url.Action helper. The third argument passed to it ensures that the browser caches the CLDR data.
    • Reference dictionaries.
    <head>
    ...
        @* execute the CldrData action method *@
        <script src="@Url.Action("CldrData", "Home", new { t = CldrDataScriptBuilder.GetCacheParam() })"></script>
        @* reference dictionaries *@
        <script src="~/js/devextreme/localization/dx.messages.de.js"></script>
        <script src="~/js/devextreme/localization/dx.messages.es.js"></script>
    </head>
    
NOTE

Demo: Using Globalize

Custom Dictionaries

Here are a few situations when you may need a custom dictionary:

  • There is no predefined dictionary for the language you require.
  • You need to change translations.
  • You need to add new messages.

To create and use a custom dictionary:

  1. Create a copy of a predefined dictionary.
  2. Update or add strings as necessary.
  3. Reference the resulting file as you would do with a predefined dictionary.

Auto Detect the Locale

You can configure controls so that they automatically detect the client browser's locale and apply the corresponding UI translation and data formatting. To do this, add the script code block provided below to Razor files where you configure DevExtreme-based controls or to a project's layout that applies to all pages in the application.

  • For Intl, call the DevExpress.localization.locale method and specify navigator.language as a parameter.

    <script>
        DevExpress.localization.locale(navigator.language);
    </script>
    
  • For Globalize, call the Globalize.locale method and specify navigator.language as a parameter.

    <script>
        Globalize.locale(navigator.language);
    </script>
    
See Also