Going international with Locale - I

The C# Column - Yashawant Kanetkar

As the number of Internet users grew worldwide, the need to create software supporting multiple languages was felt intensely because only ten percent of people use English as the primary language. People wanted applications that could communicate with them in their native language. This became simple with the release of the .NET framework.

Locale and .NET culture

Geographically speaking, a locale is a place. In software terms, a ‘locale’ is a collection of information associated with a place. Locale information includes the name and identifier of the spoken language, cultural conventions, etc. A Locale Identifier (LCID) is used to retrieve information about the locale. LCID is a 32-bit unsigned integer value that is divided into four parts. The first two parts identify the language and sub-language (sub-language corresponds to country/region) and the last two parts specify the sorting order for text strings.

The ‘culture’ in .NET refers to the user’s language and region. A culture is identified by language code–region/country code. For example, the French language spoken in France is identified by ‘fr-FR’. Here, ‘fr’ is the short form for ‘French’ and ‘FR’ is the abbreviation of France. Similarly, ‘fr-CA’ is the culture identifier for French in Canada. There are cultures that are identified by language only. These cultures are called neutral cultures. The cultures having language-region combination are called specific cultures. For example, ‘fr’ is a neutral culture, whereas, ‘fr-FR’ is a specific culture.

.NET encapsulates the culture related information in the System.Globalization and System.Resources namespaces. The object of the Globalization. CultureInfo class represents a specific culture. Using the methods of this class, we can obtain the information of the culture that is set for the current thread. The following code snippet shows how to set the culture for the current thread and obtain its name, number format and currency format.

foreach(CultureInfo c in CultureInfo.
GetCultures(CultureTypes.AllCultures))
   {
   Thread.CurrentThread.CurrentCulture = new CultureInfo(c.Name);
   Console.WriteLine ( "{0}:{1},Num:{2},Dt:{ 3}, Curr:{ 4} ",c.Name,
   c.EnglishName, (12345).ToString ("n"), (12345.50).ToString ("c"), 
   (DateTime.Now).ToShortDateString());
   } 

The CultureInfo.GetCultures( ) method returns the list of all the supported cultures. CultureTypes is an enum that contains the types of culture—specific, neutral, all cultures and only those cultures that are installed on the system. To set the culture for a thread, firstly we must obtain the reference to that thread. Here, we have obtained the reference by using the CurrentThread property of the Thread class. The two culture values of an application determine what resources are loaded for an application and how information like currency, numbers and dates are formatted. The resources loaded are determined by the UI culture setting, and the formatting options are determined by the culture setting. The Thread class provides two properties—CurrentCulture and CurrentUICulture—to change the respective culture settings. We have used the CurrentCulture property since we needed to set the culture specific formatting options. The Name and EnglishName are properties of the CultureInfo class that give the culture name and its corresponding Language (Country/Region) combination respectively. Of course, we need to use the Globalization and Threading namespaces to run this code.

Let’s now see how to localise resources. We will create a localised WinForm application that allows the user to select a language. On clicking a button another form would get displayed in the selected language. This form would contain a textbox where you can type your name. On clicking a button you would be greeted in the selected language. Our form would look as shown below.

Name the radio buttons as reng, rger, rita, and rfre respectively. Name the ‘Display’ button as bdisplay. Add the Click event handler for the ‘Display’ button. Here is the handler:

void bdisplay_Click (object sender, System.EventArgs e)
   {
   Thread t = Thread.CurrentThread;
   if(rfre.Checked)
   t.CurrentUICulture=new CultureInfo("fr-FR");
   if(rger.Checked)
   t.CurrentUICulture=new CultureInfo("de-DE");
   if(rita.Checked)
   t.CurrentUICulture=new CultureInfo("it-IT");
   if(reng.Checked)
   t.CurrentUICulture=new CultureInfo("en-US");
   greetform g=new greetform();
   g.ShowDialog();
   }

Here, we have only checked which radio button the user has selected and set the UI culture accordingly. After this we have displayed another form. We need to add this form to the project. Add controls to this form as shown alongside.

The controls and their names are given in the following table:

Add the Click event handlers for the 'Greet' and 'Close' buttons. The bgreet_Click( ) handler is given below:

void bgreet_Click (object sender, System.EventArgs e)
   {
   String s;
   DateTime t=DateTime.Now;
   if(t.Hour<=12)
   s="Good Morning";
   else
   { 
   if( t.Hour <= 19 )
   s = "Good Afternoon";
   else
   s = "Good Evening";
   } 
   s += " " + tname.Text;
   lgreet.Text = s;
   }

This handler is simple. We have only read the current system time and displayed a greeting message accordingly. Before that we have retrieved the name entered by the user in the text box and concatenated it with the message.

In the bclose_Close( ) handler call the Dispose( ) method only to close the form.

Next time we shall see what changes must be done to localise the greeting form.a

Yashavant Kanetkar, one of the first Express Computer columnists, is an established software expert, speaker and author with several best-sellers to his credit, including titles like “Let Us C” and the “Fundas” series. Contact him at kanet@nagpur.dot.net.in