Skip to main content

Localization In .NetCore MVC Application

Localization:

The translation to a specific region or country or culture or local. The websites with localization can reach a wider range of audiences.

Create A DotNet Core MVC Sample Application:

Let's learn localization steps by implementing them in a sample MVC application.


Add Sample Language Collection To AppSettings File:

In our sample let's read the different languages that we support from the appSettings.json file.
appSettings.Development.json:
"LanguageCodes": [
{
  "Name": "Spain",
  "Code": "es"
},
{
  "Name": "Mexico",
  "Code": "es-Mx"
},
{
  "Name": "United States",
  "Code": "en-us"
}
]
Let's create a type for the "LanguageCodes".
Shared/LanguageCodes: 
namespace Sample.Localization.Mvc.Shared
{
  public class LanguageCodes
  {
    public string Name { get; set; }
    public string Code { get; set; }
  }
}
Register the 'LangaugeCodes' Type in DI(Dependency Injection) services so that it can be accessed by injection.
Startup.cs:(ConfigureServices method)
services.Configure<List<LanguageCodes>>(Configuration.GetSection("LanguageCodes"));

UseRequestLocalization Middleware:

The current culture on request is set in the localization middleware(UseRequestLocalization Middleware). This middleware initializes the RequestLocalization object. On every request, middleware can read the current culture with the following type of providers.
  • QueryStringRequestCultureProvider.
  • CookieRequestCultureProvider.
  • AcceptLanguageHeaderRequestCultureProvider.
From the above providers, we need to understand that 'UseRequestLocalization' middleware tries to read the culture value from the 'query parameter' or 'cookie' or 'accept headers' as per the order we defined above.
Startup.cs:
private RequestLocalizationOptions RegisterSuportCulture()
{
  var langCodes = Configuration.GetSection("LanguageCodes").GetChildren().ToList().Select(_ => new LanguageCodes
  {
	Name = _.GetValue<string>("Name"),
	Code = _.GetValue<string>("Code")
  }).ToList();
  var localizationOptions = new RequestLocalizationOptions()
  .SetDefaultCulture(langCodes.Where(_ => _.Name == "United States")
  .Select(_ => _.Code).FirstOrDefault());
	
  return localizationOptions;
}
  • The 'UseRequestLocalization' middleware needs the 'Microsoft.AspNetCore.Builder.RequesLocalizationOption' object. The 'RequesLocalizationOption' object is used to configure all the cultures supported by our application.
  • (Line: 3-7) Reding the culture info from the 'appSettings.Development.json' file.
  • (Line: 9-11) Initialized RequestLocalizationOptions object by setting the default culture for the application.
Now register the 'UseRequestLocalization' middleware above the 'UseRouting' middleware.
Startup.cs:
app.UseRequestLocalization(RegisterSuportCulture());
app.UseRouting();

UI Dropdown To Change Culture:

In _Layout.cshtml we will configure a dropdown in the menu section to change the culture of the website.

Let's create a partial view to implement the dropdown functionality.
Views/Shared/_LanguageSelectionPartial.cshtml:
@using Microsoft.Extensions.Options
@using Sample.Localization.Mvc.Shared
@using Microsoft.AspNetCore.Localization;
@inject IOptions<List<LanguageCodes>> _languageCodes
@{
    var requestCulture = Context.Features.Get<IRequestCultureFeature>();
    var cultureName = requestCulture.RequestCulture.Culture.Name;
    var selectionItems = _languageCodes.Value.
        Select(_ => new SelectListItem {
            Text = _.Name,
            Value = _.Code,
            Selected = (_.Code.ToLower() == cultureName.ToLower()) }).ToList();
    var returnUrl = string.IsNullOrEmpty(Context.Request.Path) ? "~/" : $"~{Context.Request.Path.Value}";

}

<form id="selectLanguage" 
      asp-controller="Home" 
      asp-action="SetLanguage" 
      method="post" 
      class="form-horizontal" 
      role="form" 
      asp-route-returnUrl="@returnUrl"  >
    <select class="form-control" 
            name="culture" id="culture" 
            onchange="this.form.submit()" asp-items="selectionItems">
    </select>
</form>
  • (Line: 4) Injecting 'LanguageCodes' collection to display them in the dropdown.
  • (Line: 6) Creating an instance of the 'Microsoft.AspNetCore.Localization.IRequestCultureFeature'.
  • (Line: 7) Fetching the current culture of the application, by default it will 'United States' as we configured in the middleware.
  • (Line: 9-12) Creating dropdown item collection.
  • (Line: 13) The current application path will be passed as a post parameter on changing the dropdown value.
  • (Line: 17-28) The Html form that gets post values on changing the dropdown values. The 'asp-controller' and 'asp-action' attributes define endpoint(which we create in the next step) to post the form.
  • The 'asp-route-{your_parameter}' to pass the return URL as post value.

Culture And UI-Culture:

Dotnet supports two culture info objects like 'culture' and 'ui-culture'. The 'culture' is for translation of the text to display. The 'ui-culture' is for translation of date, time, numbers, and currency.

So we have to configure providers like 'SupportedCultures' and 'SupportedUICultures' to the RequesLocalizationOption object. So let's update our 'RegisterSuportCulture' method in the startup class.
Startup.cs:(Update RegisterSuportCulture method)
private RequestLocalizationOptions RegisterSuportCulture()
{
  var langCodes = Configuration.GetSection("LanguageCodes").GetChildren().ToList().Select(_ => new LanguageCodes
  {
	Name = _.GetValue<string>("Name"),
	Code = _.GetValue<string>("Code")
  }).ToList();
  var supportedCultures = langCodes.Select(_ => _.Code).ToArray();
  var localizationOptions = new RequestLocalizationOptions().SetDefaultCulture(langCodes.Where(_ => _.Name == "United States").Select(_ => _.Code).FirstOrDefault())
  .AddSupportedCultures(supportedCultures)
  .AddSupportedUICultures(supportedCultures);
  return localizationOptions;
}
  • (Line: 8) Creating an array of cultures.
  • (Line: 10-11) The 'AddSupportedCultures' and 'AddSupportedUICultures' configured.

MVC Endpoint Query Param Culture Redirection:

Create an MVC endpoint that get's invoked on dropdown change, this endpoint redirects us with a query parameter contains the value of the culture. Our query parameter should be like 'culture'(translation for text), 'ui-culture'(translation for the date, time, currency etc).
Controllers/HomeController.cs:
[HttpPost]
public IActionResult SetLanguage(string culture, string returnUrl)
{
  returnUrl = $"{returnUrl}?ui-culture={culture}&culture={culture}";
  return LocalRedirect(returnUrl);
}

Test UI-Culture Translation:

Let's test UI-Culture translation by adding test data on index.cshtml.
Views/Home/index.cshtml:
<h5>@DateTime.Now.ToShortDateString()</h5>
 <h5>@(Convert.ToDouble("1777.00").ToString("C2", System.Globalization.CultureInfo.CurrentCulture))</h5>

Resource File:

A resource file contains a translated string for our localization. An example of the resource file is like 'Example.resx'.

The resource file name should be fully qualified for its namespace by excluding the library name. For example, we have 'TestLocalization.dll' and we can create a resource file based on Stratup.cs file like Startup.resx,  Startup.es.resx(contains Spanish translated string). Another example of creating a resource file for HomeContorller can be done with dot notation or folder notation. Coming dot notation file names look like 'Controllers.HomeController.resx', 'Controllers.HomeController.es.resx'. Coming to folder notation file names like 'Resources/Controllers/HomeController.resx', 'Resources/Controllers/HomeController.es.resx'. Similarly, we can create resource files in views(*.cshtml) level also.

Configure Localization Service:

In the Startup.cs file add the following service for accessing and identifying the resource files localization.
Startup.cs:(Inside ConfigureServices Methods)
services.AddLocalization(options => options.ResourcesPath = "Resources");
services.
AddControllersWithViews()
.AddViewLocalization(LanguageViewLocationExpanderFormat.Suffix);
  • (Line: 1) Giving instruction to check for the resource file inside the 'Resources' folder.
  • (Line: 2) This helps to check files with culture suffix example files like 'Example.es.resx'(es culture suffix).

Culture Change Using IStringLocalizer:

The IStringLocalizer<T> has the capability to load the translated string based on culture. It has the capability to choose the resource file name based on the culture.
Controllers/HelloWorldController.cs:
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Localization;

namespace Sample.Localization.Mvc.Controllers
{
  public class HelloWorldController : Controller
  {
	private readonly IStringLocalizer<HelloWorldController> _stringLocalizer;
	public HelloWorldController(IStringLocalizer<HelloWorldController> stringLocalizer)
	{
		_stringLocalizer = stringLocalizer;
	}
	public IActionResult Index()
	{
		ViewData["Message"] = _stringLocalizer["Hello World"];
		return View();
	}
  }
}
  • (Line: 15) The 'Hello World' will be the key value of the resource file.
Here implemented resource files using dot notation as below.
For default culture no need to prefix the resource file. Here in our sample default culture is English.
Views/HelloWorld.Index.cshtml:
<h5>@ViewData["Message"]</h5>

Culture Change Using IHtmlLocalizer:

The IHtmlLocalizer has the capability to load the translated string along with Html tags in it.
Controllers/GoodMorningController.cs:
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Localization;

namespace Sample.Localization.Mvc.Controllers
{
  public class GoodMorningController : Controller
  {
	private readonly IHtmlLocalizer<GoodMorningController> _htmlLocalizer;
	public GoodMorningController(IHtmlLocalizer<GoodMorningController> htmlLocalizer)
	{
		_htmlLocalizer = htmlLocalizer;
	}
	public IActionResult Index()
	{
		ViewData["Message"] = _htmlLocalizer["Good Morning"];
		return View();
	}
  }
}
Views/GoodMorning/Index.cshtml: 
<div>
    @ViewData["Message"]
</div>
Here for this sample, we create resource files in the folder structure.


Culture Change Using IViewLocalizer:

The 'IViewLocalizer' is an interface injectable in views to load the translated string from the resource files.
Views/GoodMorning/Index.cshtml:
@using Microsoft.AspNetCore.Mvc.Localization
@inject IViewLocalizer _viewLocalizer;
 
<div>
    @_viewLocalizer["Good Morning"]
</div>
Here also we created resource file using folder notation as below.

Use Cookie For Culture Change:

Till now we have used query params to change the state of the culture, now we will update our sample to use cookie to save the culture info.
Controllers/HomeController.cs:(Update SetLanguage Action Method)
[HttpPost]
public IActionResult SetLanguage(string culture, string returnUrl)
{
  Response.Cookies.Append(
   CookieRequestCultureProvider.DefaultCookieName,
   CookieRequestCultureProvider.MakeCookieValue(new RequestCulture(culture)),
   new CookieOptions { Expires = DateTimeOffset.UtcNow.AddYears(1) }
  );
  return LocalRedirect(returnUrl);
}
That's all about the different approaches to make an application localizable.

Support Me!
Buy Me A Coffee PayPal Me

Wrapping Up:

Hopefully, I think this article delivered some useful information on the localizing an AspNetCore Mvc application. I love to have your feedback, suggestions, and better techniques in the comment section below.

Follow Me:

Labels:

Comments

Post a Comment

Popular posts from this blog

Angular 14 Reactive Forms Example

In this article, we will explore the Angular(14) reactive forms with an example. Reactive Forms: Angular reactive forms support model-driven techniques to handle the form's input values. The reactive forms state is immutable, any form filed change creates a new state for the form. Reactive forms are built around observable streams, where form inputs and values are provided as streams of input values, which can be accessed synchronously. Some key notations that involve in reactive forms are like: FormControl - each input element in the form is 'FormControl'. The 'FormControl' tracks the value and validation status of form fields. FormGroup - Track the value and validate the state of the group of 'FormControl'. FormBuilder - Angular service which can be used to create the 'FormGroup' or FormControl instance quickly. Form Array - That can hold infinite form control, this helps to create dynamic forms. Create An Angular(14) Application: Let'
3 comments
Read more

.NET 7 Web API CRUD Using Entity Framework Core

In this article, we are going to implement a sample .NET 7 Web API CRUD using the Entity Framework Core. Web API: Web API is a framework for building HTTP services that can be accessed from any client like browser, mobile devices, and desktop apps. In simple terminology API(Application Programming Interface) means an interface module that contains programming functions that can be requested via HTTP calls either to fetch or update data for their respective clients. Some of the Key Characteristics of API: Supports HTTP verbs like 'GET', 'POST', 'PUT', 'DELETE', etc. Supports default responses like 'XML' and 'JSON'. Also can define custom responses. Supports self-hosting or individual hosting, so that all different kinds of apps can consume it. Authentication and Authorization are easy to implement. The ideal platform to build the REST full services. Install The SQL Server And SQL Management Studio: Let's install the SQL server on our l
3 comments
Read more

ReactJS(v18) JWT Authentication Using HTTP Only Cookie

In this article, we will implement the ReactJS application authentication using the HTTP-only cookie. HTTP Only Cookie: In a SPA(Single Page Application) Authentication JWT token either can be stored in browser 'LocalStorage' or in 'Cookie'. Storing the JWT token inside of the cookie then the cookie should be HTTP Only. The HTTP-ONly cookie nature is that it will be only accessible by the server application. Client apps like javascript-based apps can't access the HTTP-Only cookie. So if we use the authentication with HTTP-only JWT cookie then we no need to implement the custom logic like adding authorization header or storing token data, etc at our client application. Because once the user authenticated cookie will be automatically sent to the server by the browser on every API call. Authentication API: To authenticate our client application with JWT HTTP-only cookie, I developed a NetJS(which is a node) Mock API. Check the GitHub link and read the document on G
3 comments
Read more

.NET6 Web API CRUD Operation With Entity Framework Core

In this article, we are going to do a small demo on AspNetCore 6 Web API CRUD operations. What Is Web API: Web API is a framework for building HTTP services that can be accessed from any client like browser, mobile devices, desktop apps. In simple terminology API(Application Programming Interface) means an interface module that contains a programming function that can be requested via HTTP calls to save or fetch the data for their respective clients. Some of the key characteristics of API: Supports HTTP verbs like 'GET', 'POST', 'PUT', 'DELETE', etc. Supports default responses like 'XML' and 'JSON'. Also can define custom responses. Supports self-hosting or individual hosting, so that all different kinds of apps can consume it. Authentication and Authorization are easy to implement. The ideal platform to build REST full services. Create A .NET6 Web API Application: Let's create a .Net6 Web API sample application to accomplish our
6 comments
Read more

Angular 14 State Management CRUD Example With NgRx(14)

In this article, we are going to implement the Angular(14) state management CRUD example with NgRx(14) NgRx Store For State Management: In an angular application to share consistent data between multiple components, we use NgRx state management. Using NgRx state helps to avoid unwanted API calls, easy to maintain consistent data, etc. The main building blocks for the NgRx store are: Actions - NgRx actions represents event to trigger the reducers to save the data into the stores. Reducer - Reducer's pure function, which is used to create a new state on data change. Store - The store is the model or entity that holds the data. Selector - Selector to fetch the slices of data from the store to angular components. Effects - Effects deals with external network calls like API. The effect gets executed based the action performed Ngrx State Management flow: The angular component needs data for binding.  So angular component calls an action that is responsible for invoking the API call.  Aft
8 comments
Read more

Angular 14 Crud Example

In this article, we will implement CRUD operation in the Angular 14 application. Angular: Angular is a framework that can be used to build a single-page application. Angular applications are built with components that make our code simple and clean. Angular components compose of 3 files like TypeScript File(*.ts), Html File(*.html), CSS File(*.cs) Components typescript file and HTML file support 2-way binding which means data flow is bi-directional Component typescript file listens for all HTML events from the HTML file. Create Angular(14) Application: Let's create an Angular(14) application to begin our sample. Make sure to install the Angular CLI tool into our local machine because it provides easy CLI commands to play with the angular application. Command To Install Angular CLI npm install -g @angular/cli Run the below command to create the angular application. Command To Create Angular Application ng new name_of_your_app Note: While creating the app, you will see a noti
5 comments
Read more

Unit Testing Asp.NetCore Web API Using xUnit[.NET6]

In this article, we are going to write test cases to an Asp.NetCore Web API(.NET6) application using the xUnit. xUnit For .NET: The xUnit for .Net is a free, open-source, community-focused unit testing tool for .NET applications. By default .Net also provides a xUnit project template to implement test cases. Unit test cases build upon the 'AAA' formula that means 'Arrange', 'Act' and 'Assert' Arrange - Declaring variables, objects, instantiating mocks, etc. Act - Calling or invoking the method that needs to be tested. Assert - The assert ensures that code behaves as expected means yielding expected output. Create An API And Unit Test Projects: Let's create a .Net6 Web API and xUnit sample applications to accomplish our demo. We can use either Visual Studio 2022 or Visual Studio Code(using .NET CLI commands) to create any.Net6 application. For this demo, I'm using the 'Visual Studio Code'(using the .NET CLI command) editor. Create a fo
7 comments
Read more

Part-1 Angular JWT Authentication Using HTTP Only Cookie[Angular V13]

In this article, we are going to implement a sample angular application authentication using HTTP only cookie that contains a JWT token. HTTP Only JWT Cookie: In a SPA(Single Page Application) Authentication JWT token either can be stored in browser 'LocalStorage' or in 'Cookie'. Storing JWT token inside of the cookie then the cookie should be HTTP Only. The HTTP-Only cookie nature is that it will be only accessible by the server application. Client apps like javascript-based apps can't access the HTTP-Only cookie. So if we use authentication with HTTP only JWT cookie then we no need to implement custom logic like adding authorization header or storing token data, etc at our client application. Because once the user authenticated cookie will be automatically sent to the server by the browser on every API call. Authentication API: To implement JWT cookie authentication we need to set up an API. For that, I had created a mock authentication API(Using the NestJS Se
Post a Comment
Read more

ReactJS(v18) Authentication With JWT AccessToken And Refresh Token

In this article, we are going to do ReactJS(v18) application authentication using the JWT Access Token and Refresh Token. JSON Web Token(JWT): JSON Web Token is a digitally signed and secured token for user validation. The JWT is constructed with 3 important parts: Header Payload Signature Create ReactJS Application: Let's create a ReactJS application to accomplish our demo. npx create-react-app name-of-your-app Configure React Bootstrap Library: Let's install the React Bootstrap library npm install react-bootstrap bootstrap Now add the bootstrap CSS reference in 'index.js'. src/index.js: import 'bootstrap/dist/css/bootstrap.min.css' Create A React Component 'Layout': Let's add a React component like 'Layout' in 'components/shared' folders(new folders). src/components/shared/Layout.js: import Navbar from "react-bootstrap/Navbar"; import { Container } from "react-bootstrap"; import Nav from "react-boot
Post a Comment
Read more

A Small Guide On NestJS Queues

NestJS Application Queues helps to deal with application scaling and performance challenges. When To Use Queues?: API request that mostly involves in time taking operations like CPU bound operation, doing them synchronously which will result in thread blocking. So to avoid these issues, it is an appropriate way to make the CPU-bound operation separate background job.  In nestjs one of the best solutions for these kinds of tasks is to implement the Queues. For queueing mechanism in the nestjs application most recommended library is '@nestjs/bull'(Bull is nodejs queue library). The 'Bull' depends on Redis cache for data storage like a job. So in this queueing technique, we will create services like 'Producer' and 'Consumer'. The 'Producer' is used to push our jobs into the Redis stores. The consumer will read those jobs(eg: CPU Bound Operations) and process them. So by using this queues technique user requests processed very fastly because actually
8 comments
Read more