Microsoft ASP.NET Localization

This page describes how to get ASP.NET applications to display text and images in multiple languages.

.NET Internationalization (I18N)

Unlike PHP, Microsoft's ASP.NET was designed to natively support Unicode which can display the character sets of all languages in the world.

The trouble with internationalizing ASP.NET applications is that several approaches are available.

Microsoft initial 1.1 release of .NET required coding ResourceManager.

Organizing Resource Strings

ResXFileCodeGenerator

satellite assembly (.dll file)

This generates a .NET managed ResourceManager class that exposes every resource in the *.resx file as a strongly typed static property of the Microsoft Core Library (mscorlib.dll) ResourceManager class which looks up culture-specific resources.

It has a return type System.Resources.ResourceManager

To retrieve culture-specific resources, this code is inserted:

Build Action has value of Embedded Resource ???

To support versioning the main assembly without redeploying satellites, the SatelliteContractVersionAttribute is specified.
To avoid looking up a satellite assembly that might never exist, the NeutralResourcesLanguageAttribute is specified.

The Windows Forms Resource Editor (Winres.exe) tool within the Windows Software Development Kit (SDK) supports localization of Windows Forms dialogs.

Resource Generation using ResGen.exe

MSDN article on ResGen

Resource Generation using GenerateResource Task

MSDN article notes that it follows links in .resx files and checks timestamps in them as well. <LogicalName>someQualifier.someResource.resources</LogicalName>

Assembly Linker Tool

Microsoft MSDN on Assembly Linker is built into the VS 2008 compiler.

Single Assembly Customized Custom Tool

If the application is translated into 17 languages, then there will be that many satellite assemblies for each assembly in the app.

This is a problem of performance because each satellite assembly file takes some time to load, making an application internationalized in the default way take significantly longer to start-up.

The problem is that the class was created with an internal. access modified, which means only classes within the assembly can access its properties (translated resource strings).

TOOL: This problem was solved bu Dmytro Kryvko and friends, who provide a way for .NET to only load a single assembly which code in other assemblies can reference to obtain translated strings. He reverse-engineered Microsoft's version of ResXFileCodeGenerator to change its class access modifier to public (from internal), and adding some enhancements along the way. It is available within page Extended Strongly Typed Resource Generator.

The down-side of this approach is that to make use of it, two COM objects must be copied onto and registered on every web server (by someone with administrator privileges).

ResXFileCodeGeneratorEx — A custom tool generating public resource wrappers.
InternalResXFileCodeGeneratorEx — A custom tool generating internal resource wrappers.

Source is provided along with the COM object installer. It uses namespace "DMKSoftware.CodeGenerators". Author Dmytro (who works for Corrigo), has been actively maintaining the software since 2006.

Another down-side with this approach is that de-compilation and modification may need to occur with each new version of .NET which Microsoft puts out, since Microsoft may decide to change the error messages which needs to be ignored by the modified module, such as:

[SuppressMessageAttribute( "Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]

Visual Studio .NET 2008 introduces a new custom tool called PublicResXFileCodeGenerator to generate public resource class wrappers.

Is this is the approach with Visual Studio 2010 and .NET 4.0?

Localization of ASP.NET AJAX Apps

There are several strategies:

Use built-in facilities of Calendar and other controls.
App_LocalResource folder created within VS (from Tools > Generate Local Resource) after selecting a specific .aspx file. This is typically used for localizing text for menu items and controls. These have meta:resource attributes. Default.asps.resx
App_GlobalResource after right-clicking on the web project/application and selecting Add > Add ASP.NET Folder >
HTTP Handler
Resources file, which does not require a recompile for a change in text.
Regular Expresson Text Replacement
Database

Luciano Sampaio from Brazil. part 2 Introduction

TOOL: GACutil.exe

The zip file also contains a Globalization folder containing a .js file for each of the 137 (language + country) cultures .NET supports by default.
TIP: Immediately after download, rename the file to add the release date, such as 2009_05_13 (for May 13, 2009).

In ASP.NET 2.0, to implicitly obtain localized text specific to a particular page:
<asp:Label id=lblWelcome meta:resourcekey="lblWelcome" Text="Welcome" runat="server"> </asp:Label>

You only need to set the values (Control.Property) of different fields for each control in the Visual Studio resource file editor.

In ASP.NET 2.0, to explicitly obtain localized text:
String welcome = Assembly.class.Welcome;
lblWelcome.Text = Assembly.class.Welcome;

CultureInfo in HTML

When you see something like this in HTML returned from a ASP.NET server:

var __cultureInfo = '{"name":"fr-BE", ....

The EnableScriptGlobalization="true" property was specified by the developer so that ScriptManager makes use of the Language setting that Internet browsers send to servers in request headers.

By default it's "en-US" for English in the US. But some set it to other cultures for web sites which recognizes it. Facebook recognizes it.

The values are obtained from the Globalization folder of the Framework.

Localized Assembly Files

A Web Application Project contains an Assembly, which (among other things) specifies localized resource (.rex) files used in the project.

A Web Site Project does not contain an Assembly. Because of this,
A Web Site Project cannot use localized resource (.rex) files specified in an assembly. ???

Localized JavaScript Files

When a particular culture requires a different ordering of words than the neutral culture (English), a unique JavaScript file may need to be created for it. The ScriptManager automatically looks for a JavaScript file unique to a ResourceUICultures when it is specified with its child ScriptReference tag. The <asp:ScriptReference Assembly appears in the .aspx file's Design view within Properties viewr Behavior Scripts (Collection).

<Scripts>
	<asp:ScriptReference Name="MicrosoftAjax.js"
    Path="~/AjaxFramework/MicrosoftAjax.js" ResourceUICultures="fr"/>
</Scripts>

Notice that these are in a AjaxFramework folder created in each project, and contains a Debug version copied from the AjaxFramework folder within C:\Programs\Microsoft.

Additionally, there are debug versions of JavaScript files.

Thus, this is a typical cause of human mistakes and therefore error messages.

Introduction to Localization in ASP.NET 2.0 by Rick Strahl, who developed a database app to retrieve localized strings.
.NET Internationalization Book by Guy Smith Ferrier
ASP.NET 2.0 Localization: A Fresh Approach to Localizing Web Applications by Michelle Leroux Bustamante. This reviews use of VS2005's Generate Local Resource (from the Tools menu) to generate .resx files in App_LocalResources.
Localizing StyleSheets via HTTPHandler
DbResourceProvider to localize by defining localized resource files as part of Hawaiian Rick Strahl's commercial West Wind Web Toolkit for ASP.NET.

Your rating of this page:
Low High

Your comments on this topic, please:

Publish this comment publicly

Your first name:

Your family name:

Your location (city, country):

Your Email address:

Email me updates

Top of Page

Thank you!