Professional ASP.NET 3.5 in C# and Visual Basic Part 143 pdf

From this figure, you can see that the en-US culture is the default setting in which the ASP.NET thread executes.. In this case, the results are presented for the Thai language in Thaila

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Response.Write("Culture’s Parent Name: " & ci.Parent.Name.ToString() & _

" ")

Response.Write("Culture’s Display Name: " & ci.DisplayName.ToString() & _

" ")

Response.Write("Culture’s English Name: " & ci.EnglishName.ToString() & _

" ")

Response.Write("Culture’s Native Name: " & ci.NativeName.ToString() & _

" ")

Response.Write("Culture’s Three Letter ISO Name: " & _

ci.Parent.ThreeLetterISOLanguageName.ToString() & " ")

Response.Write("Calendar Type: " & ci.Calendar.ToString() & "")

End Sub

C#

protected void Page_Load(object sender, EventArgs e)

{

CultureInfo ci = System.Threading.Thread.CurrentThread.CurrentCulture;

Response.Write("CURRENT CULTURE’S INFO");

Response.Write("Culture’s Name: " + ci.Name.ToString() + " ");

Response.Write("Culture’s Parent Name: " + ci.Parent.Name.ToString() +

" ");

Response.Write("Culture’s Display Name: " + ci.DisplayName.ToString() +

" ");

Response.Write("Culture’s English Name: " + ci.EnglishName.ToString() +

" ");

Response.Write("Culture’s Native Name: " + ci.NativeName.ToString() +

" ");

Response.Write("Culture’s Three Letter ISO Name: " +

ci.Parent.ThreeLetterISOLanguageName.ToString() + " ");

Response.Write("Calendar Type: " + ci.Calendar.ToString() + "");

}

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This bit of code in thePage_Loadevent checks theCurrentCultureproperty You can place the result

of this value in aCultureInfoobject To get at this object, you import theSystem.Globalization

namespace into your Web page TheCultureInfoobject contains a number of properties that provides you with specific culture information The following items, which are displayed in a series of simple

Response.Writestatements, are only a small sampling of what is actually available Running this page produces results similar to what is shown in Figure 30-2

From this figure, you can see that the en-US culture is the default setting in which the ASP.NET thread executes In addition to this, you can use theCultureInfoobject to get at a lot of other descriptive infor-mation about the culture

You can always change a thread’s culture on the overloads provided via a new instantiation of the

CultureInfoobject This is presented in Listing 30-2

Listing 30-2: Changing the culture of the thread using the CultureInfo object

VB

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)

System.Threading.Thread.CurrentThread.CurrentCulture = New CultureInfo("th-TH")

Dim ci As CultureInfo = System.Threading.Thread.CurrentThread.CurrentCulture

Response.Write("CURRENT CULTURE’S INFO")

Response.Write("Culture’s Name: " & ci.Name.ToString() & " ")

Response.Write("Culture’s Parent Name: " & ci.Parent.Name.ToString() & _

" ")

Response.Write("Culture’s Display Name: " & ci.DisplayName.ToString() & _

" ")

Response.Write("Culture’s English Name: " & ci.EnglishName.ToString() & _

" ")

Response.Write("Culture’s Native Name: " & ci.NativeName.ToString() & _

" ")

Response.Write("Culture’s Three Letter ISO Name: " & _

ci.Parent.ThreeLetterISOLanguageName.ToString() & " ")

Response.Write("Calendar Type: " & ci.Calendar.ToString() & "")

End Sub

C#

{

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("th-TH");

CultureInfo ci = System.Threading.Thread.CurrentThread.CurrentCulture;

Response.Write("CURRENT CULTURE’S INFO");

Response.Write("Culture’s Name: " + ci.Name.ToString() + " ");

Response.Write("Culture’s Parent Name: " + ci.Parent.Name.ToString() +

" ");

Response.Write("Culture’s Display Name: " + ci.DisplayName.ToString() +

" ");

Response.Write("Culture’s English Name: " + ci.EnglishName.ToString() +

" ");

Response.Write("Culture’s Native Name: " + ci.NativeName.ToString() +

" ");

Response.Write("Culture’s Three Letter ISO Name: " +

ci.Parent.ThreeLetterISOLanguageName.ToString() + " ");

Response.Write("Calendar Type: " + ci.Calendar.ToString() + "");

}

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In this example, only a single line of code is added to assign a new instance of theCultureInfoobject to

theCurrentCultureproperty of the thread being executed by ASP.NET The culture setting enables the

CultureInfoobject to define the culture you want to utilize In this case, the Thai language of Thailand

is assigned, and the results produced in the browser are illustrated in Figure 30-3

Figure 30-3

From this figure, you can see that the NET Framework goes so far as to provide the native name

of the language used even if it is not a Latin-based letter style In this case, the results are presented for

the Thai language in Thailand, and some of the properties that are associated with this culture (such as

an entirely different calendar than is the one used in Western Europe and the United States) Remember

that you referenceSystem.Globalizationto get at theCultureInfoobject

Server-Side Culture Declarations

ASP.NET enables you to easily define the culture that is used either by your entire ASP.NET

applica-tion or by a specific page within your applicaapplica-tion You can specify the culture for any of your ASP.NET

applications by means of the appropriate configuration files In the default install of ASP.NET, no culture

is specified as is evident when you look at the globalweb.config.commentsfile (meant for

documen-tation purposes) found in the ASP.NET 2.0 CONFIG folder (C:\WINDOWS\Microsoft.NET\Framework\

v2.0.50727\CONFIG) Remember that ASP.NET 3.5 is built on top of ASP.NET 2.0 and uses the same

configuration files In theweb.config.commentsfile, you find a<globalization>section of the

config-uration document This section is presented in Listing 30-3

Listing 30-3: The <globalization> section in the web.config.comments file

<globalization requestEncoding="utf-8" responseEncoding="utf-8" fileEncoding=""

culture="" uiCulture="" enableClientBasedCulture="false"

responseHeaderEncoding="utf-8" resourceProviderFactoryType=""

enableBestFitResponseEncoding="false" />

Note the two attributes represented in bold —cultureanduiCulture Thecultureattribute enables

you to define the culture to use for processing incoming requests, whereas theuiCultureattribute

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enables you define the default culture needed to process any resource files in the application (The use of these attributes will be covered later in the chapter.)

As you look at the configuration declaration in Listing 30-3, you can see that nothing is specified for the culture settings One option you have when specifying a culture on the server is to define this culture

in the server version of theweb.configfile found in the CONFIG folder This causes every ASP.NET

3.5 application on this server to adopt this particular culture setting The other option is to specify these settings in theweb.configfile of the application as illustrated in Listing 30-4

Listing 30-4: Defining the <globalization> section in the web.config file

<system.web>

</system.web>

</configuration>

In this case, the culture established for just this ASP.NET application is the Russian language in the

country of Russia In addition to setting the culture at either the server-wide the application-wide level, another option is to set the culture at the page-level This is illustrated in Listing 30-5

Listing 30-5: Defining the culture at the page level @page using the directive

<%@ Page Language="VB" UICulture="ru-RU" Culture="ru-RU" %>

This example determines that the Russian language and culture settings are used for everything on the page You can see this in action by using this@Pagedirective and a simple calendar control on the page Figure 30-4 shows the output

Figure 30-4

Client-Side Culture Declarations

In addition to using server-side setting to define the culture for your ASP.NET pages, you also have the option of defining the culture with what the client has set as his preference in a browser instance

When end users install Microsoft’s Internet Explorer and some of the other browsers, they have the

option to select their preferred cultures in a particular order (if they have selected more than a single

culture preference) To see this in action in IE, select Tools ➪ Internet Options from the IE menu On the

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first tab provided (General), you see a Languages button at the bottom of the dialog Select this button

and you are provided with the Language Preference dialog shown in Figure 30-5

In this figure, you can see that two cultures are selected from the list of available cultures To add any

additional cultures to the list, select the Add button from the dialog and select the appropriate culture

from the list After you have selected cultures that are present in the list, you can select the order in

which you prefer to use them In the case of Figure 30-5, the Finnish culture is established as the most

preferred culture, whereas the U.S version of English is selected as the second preference A user with

this setting gets the Finnish language version of the application before anything else; if a Finnish version

is not available, a U.S English version is presented

Figure 30-5

After the end user selects, you can use the auto feature provided in ASP.NET 3.5 Instead of specifying

a distinct culture in any of the configuration files or from the@Pagedirective, you can also state that

ASP.NET should automatically select the culture provided by the end user requesting the page This is

done using theautokeyword, as illustrated in Listing 30-6

Listing 30-6: Changing the culture to the end user’s selection

<%@ Page Language="VB" UICulture="auto" Culture="auto" %>

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With this construction in your page, the dates, calendars, and numbers now appear in the preferred cul-ture of the requestor What happens, however, if you have translated resources in resource files (shown later in the chapter) that depends on a culture specification What if you only have specific translations

and so cannot handle every possible culture that might be returned to your ASP.NET page? In this case, you can specify the auto option with an additional fallback option if ASP.NET cannot find the culture

settings of the user (such as culture-specific resource files) This usage is illustrated in Listing 30-7

Listing 30-7: Providing a fallback culture from the auto option

<%@ Page Language="VB" UICulture="auto:en-US" Culture="auto:en-US" %>

In this case, the automatic detection is utilized, but if the culture the end user prefers is not present, then en-US is used

Translating Values and Behaviors

In the process of globalizing your ASP.NET application, you may notice a number of items that are

done differently than building an application that is devoid of globalization, including how dates are

represented and currencies are shown This next section touches upon some of these topics

Understanding Differences in Dates

Different cultures specify dates and time very differently For instance, take the following date as an

example:

08/11/2008

What is this date exactly? Is it August 11, 2008 or is it November 8, 2008I repeat: When storing values

such as date/time stamps in a database or other some type of back-end system, you should always use the same culture (or invariant culture) for these items so that you avoid any mistakes It should be the job

of the business logic layer or the presentation layer to convert these items for use by the end user

Setting the culture at the server-level or in the@Pagedirective (as was discussed earlier) enables ASP.NET

to make these conversions for you You can also simply assign a new culture to the thread in which

ASP.NET is running For instance, look at the code listing presented in Listing 30-8

Listing 30-8: Working with date/time values in different cultures

VB

Dim dt As DateTime = New DateTime(2008, 8, 11, 11, 12, 10, 10)

System.Threading.Thread.CurrentThread.CurrentCulture = New CultureInfo("en-US")

Response.Write("en-US ")

Response.Write(dt.ToString() & " ")

System.Threading.Thread.CurrentThread.CurrentCulture = New CultureInfo("ru-RU")

Response.Write("ru-RU ")

System.Threading.Thread.CurrentThread.CurrentCulture = New CultureInfo("fi-FI")

Continued

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System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("th-TH")

Response.Write("th-TH ")

Response.Write(dt.ToString())

End Sub

C#

{

DateTime dt = new DateTime(2008, 8, 11, 11, 12, 10, 10);

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("en-US");

Response.Write("en-US ");

Response.Write(dt.ToString() + " ");

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("ru-RU");

Response.Write("ru-RU ");

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("fi-FI");

Response.Write("fi-FI ");

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("th-TH");

Response.Write("th-TH ");

Response.Write(dt.ToString());

}

In this case, four different cultures are utilized, and the date/time construction used by that culture is

written to the browser screen using aResponse.Writecommand The result from this code operation

is presented in Figure 30-6

Figure 30-6

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As you can see, the formats used to represent a date/time value are dramatically different from one

another — and one of the cultures, the Thai culture (th-TH), even uses an entirely different calendar that labels this year as 2551

Understanding Differences in Numbers and Currencies

In addition to date/time values, numbers are constructed quite differently from one culture to the next How can a number be represented differently in different cultures? Well, it has less to do with the actual number (although certain cultures use different number symbols), and more to do with how the number separators are used for decimals or for showing amounts such as thousands, millions, and more For

instance, in the English culture of the United States (en-US), you see numbers represented in the following fashion:

5,123,456.00

From this example, you can see that the en-US culture uses a comma as a separator for thousands and a period for signifying the start of any decimals that might appear after the number is presented It is quite different when working with other cultures Listing 30-9 shows you an example of representing numbers

in other cultures

Listing 30-9: Working with numbers in different cultures

VB

Dim myNumber As Double = 5123456.00

Response.Write(myNumber.ToString("n") & " ")

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("vi-VN")

Response.Write("vi-VN ")

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("fi-FI")

Response.Write("fi-FI ")

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("fr-CH")

Response.Write("fr-CH ")

Response.Write(myNumber.ToString("n"))

End Sub

C#

{

double myNumber = 5123456.00;

Response.Write(myNumber.ToString("n") + " ");

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("vi-VN");

Response.Write("vi-VN ");

Continued

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System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("fr-CH");

Response.Write("fr-CH ");

Response.Write(myNumber.ToString("n"));

}

Running this short example produces the results presented in Figure 30-7

Figure 30-7

From this example, you can see that the other cultures represented here show numbers in quite a different

format than that of the en-US culture The second culture listed in the figure, vi-VN (Vietnamese in

Viet-nam), constructs a number exactly the opposite from the way it is constructed in en-US The Vietnamese

culture uses periods for the thousand separators and a comma for signifying decimals Finnish, on the

other hand, uses spaces for the thousand separators and a comma for the decimal separator, whereas

the French-speaking Swiss use a high comma for separating thousands and a period for the decimal

sep-arator As you can see, it is important to ‘‘translate’’ numbers to the proper construction so that users of

your application can properly understand the numbers represented

You also represent numbers is when working with currencies It is one thing to convert currencies so that

end users understand the proper value of an item, but it is another to translate the construction of the

currency just as you would a basic number

Each culture has a distinct currency symbol used to signify that a number represented is an actual

cur-rency value For instance, the en-US culture represents a curcur-rency in the following format:

$5,123,456.00

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The en-US culture uses a U.S Dollar symbol ($), and the location of this symbol is just as important

as the symbol itself For en-US, the $ symbol directly preceeds the currency value (with no space in

between the symbol and the first character of the number) Other cultures use different symbols to rep-resent a currency and often place those currency symbols in different locations Change the previous

Listing 30-9 so that it now represents the number as a currency The necessary changes are presented

in Listing 30-10

Listing 30-10: Working with currencies in different cultures

VB

Dim myNumber As Double = 5123456.00

Response.Write(myNumber.ToString("c") & " ")

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("vi-VN")

Response.Write("vi-VN ")

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("fi-FI")

Response.Write("fi-FI ")

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("fr-CH")

Response.Write("fr-CH ")

Response.Write(myNumber.ToString("c"))

End Sub

C#

{

double myNumber = 5123456.00;

Response.Write(myNumber.ToString("c") + " ");

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("vi-VN");

Response.Write("vi-VN ");

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("fr-CH");

Response.Write("fr-CH ");

Response.Write(myNumber.ToString("c"));

}

Run this example to see how these cultures represent currency values, as illustrated in Figure 30-8

From this figure, you can see that not only are the numbers constructed quite differently from one

another, but the currency symbol and the location of the symbol in regard to the number are quite differ-ent as well

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