C# 5.0 Programmer's Reference

Resource Files ❘ 407
Localization Resources
One of the most important reasons for inventing resource files was to allow localization: supporting
different text, images, and other items for different languages and cultures. Resources make localization
in Visual Studio .NET easy.
First, create a form using whatever language you typically use from day to day. For me, that’s English
as spoken in the United States. Open the form in the form designer and give it whatever controls you
need. Set the form’s and controls’ properties as usual.
Next, set the form’s Localizable property to true and set the form’s Language property to the
first language you want to support other than the default language that you have been working
with so far. Modify the controls’ properties for the new language.
As you modify a form, Visual Studio saves the changes you make to a new resource file attached to
the form. If you open Solution Explorer and expand the form’s entry, you can see these resource files
below the form’s file.
Example program Localized uses default settings for United States English. It also includes localizations
for generic German (as opposed to German as spoken in Switzerland, Germany, Liechtenstein,
or some other country). If you expand the form’s entry in Solution Explorer, you’ll find the files
Form1.resx holding the default settings and Form1.de.resx holding the German settings.
When you build the program, Visual Studio compiles the resources and saves them in a DLL file
named Localized.resources.dll in a directory named after the locale. (The “Localized” part of the file’s
name comes from the program’s name.) At run time, the application automatically checks the computer’s
regional settings and selects the resource file that matches most closely.
For example, suppose your computer is configured for the German/Switzerland (de-CH) locale.
The program first looks for Localized.resources.dll in a subdirectory named de-CH. If it doesn’t
find the DLL, it looks for the generic German resources DLL in the subdirectory de (the code for
generic German). If the program still can’t find a resource DLL, it uses the default implementation
that is included in the form itself.
Later, if you need to modify the resources for a locale, you can rebuild the application and then copy
the new Localized.resources.dll into the appropriate subdirectory.
Normally, you should let the application pick the appropriate resource file automatically, but you
can explicitly select a resource file for testing purposes. To do that, open the form’s code file and
add the following using directives.
using System.Threading;
using System.Globalization;
Next, find the form’s constructor and add the bold lines shown in the following code.
public Form1()
{
// Set the culture and UI culture to German.
Thread.CurrentThread.CurrentCulture = new CultureInfo("de-DE");
Thread.CurrentThread.CurrentUICulture = new CultureInfo("de-DE");
}
InitializeComponent();
www.it-ebooks.info