ASPNET 2'0 Internationalization

1
i18n (Internationalization)in ASP.NET 2.0
Mark FrederiksenABLE Innovations
2
Objectives

• Describe the Internationalization issues related
  to ASP.NET 2.0 applications
• Define technical approaches
• Suggest strategies for Internationalizing ASP.NET
  2.0 applications (and WinForms, too)

3
Assumptions Environment

• ASP.NET 2.0 development environment
• Using Visual Studio 2005 C
• Microsoft SQL Server 2005
• Typically, single or clustered server environment
  supporting multiple languages simultaneously
• Unicode as default code set
• Likely Using ASP.NET 2.0 Membership/Profile
  capabilities

4
Assumptions Users

• Using browsers
• Internet Explorer 6.0 (Windows and Mac??)
• Firefox 1.5 (Windows and Mac)
• Safari 1.3.2 (Mac)
• Languages initially supported
• Unicode as default code set
• English (default)
• Western European languages
• Asian Japanese, Korean, Chinese
  (simplified (PRC), traditional (Taiwan, other
  areas)
• Discussion will NOT include bi-directional
  language
• Only Gregorian calendar system will be considered
• Most Users are not on local LAN - not dependant
  upon AD

5
Primary Steps

• Enable International options (SQL Server)
• Establish the users preferred culture
• Respond to the users culture
• Resources and Formatting
• Resource translation
• Test and Maintain system

6
SQL Server Issues

• Enable Unicode
• Establish the Collate options

7
SQL Server 2005 Default Internationalization
Settings

• Default internationalization behavior is
  determined by
• SQL Installation
• Install asks for default Character set and
  Collation - Affects System database
  Choosing Unicode would double system
  databases
• - Hard to change after SQL Server is installed
• Suggest using DEFAULTS Windows Latin-1
  char. Set Latin1_General collation
  
• Defining a new database
• Defaults to model database
• - which defaults to SQL Installation Char
  set/Collation unless model database has been
  altered
• Suggest using DEFAULTS

8
SQL Server 2005 Data Columns

• Use Unicode datatypes in Table columns,
  CONVERT() and CAST() operations
• nchar
• nvarchar
• nvarchar(max)
• ntext
• Catalog view sys.types reports length in bytes,
  not characters
• Substitute ASCII() and CHAR() with UNICODE()
  and NCHAR()
• Define variables and parameters of Stored
  Procedure and triggers in Unicode
• Prefix Unicode string constants with the letter
  N
• Important even if the column name being
  references is Unicode e.g. EXECUTE Product_Info
  _at_name NChain

9
SQL Server 2005 Unicode

• SQL Server 2005 uses UCS-2
• Some characters not included Additional
  Chinese characters
• SQL Server stores these as supplementary
  characters - stored as two unified Unicode
  character
• Supplementary characters sorted in 90 series
  collations
• Japnese_90
• Korean_90
• Chinese_PRC_90 Chinese_PRC_Stroke_90
• Chinese_Taiwan_Bopomofo_90 Chinese_Taiwan_Stroke_9
  0
• Chinese_Hong_Kong_Stroke_90_CI_AS

10
SQL Server 2005 Collation

• SQL Server 2005 uses two collation Types
• Windows Collation
• Defined to support Windows locales
• Uses the same code pages, sorting, comparisons as
  an application on a Windows system
• Recommended if you mix Unicode and non-Unicode
  columns in the database applies Unicode based
  sorting rules to both Unicode and non-Unicode
  data (internally converts non-Unicode data to
  Unicode for comparison operations), unlike SQL
  Collations
• Default setting Latin1_General supports 33
  locales
• SQL Collations Legacy for prior SQL versions
• Sorts Unicode fields as Unicode, and non-Unicode
  as non-Unicode

11
SQL Server 2005 Sorting Order

• Sort order concepts
• Three sort values
• Primary value basic character ignoring case
  and accents
• Secondary value A a
• Tertiary value - typically accents
• Options
• Case Sensitive
• Accent Sensitive
• Kana sensitive distinguish between Japanese
  Kana and Hiragana
• Width sensitive - distinguish between half-width
  and full-width chars.
• Binary Binary Code

12
SQL Server 2005 SQL statements

• Specifying Collation in SQL
• Collate clause
• Example
• SELECT name FROM customer ORDER BY name COLLATE
  Japanese_Unicode
• Append options
• _CS _CI Case sensitive Case insensitive
• _AS _AI Accent sensitive Accent inensitive
• _KS Kana sensitive, if omitted, Kana
  insensitive
• _WS Width sensitive, if omitted, width
  insensitive
• Examples Latin1_General_CI_AS

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Establish the Users preferred culture
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Culture

• Description of a language, and OPTIONALLY a
  region
• System.Globalization.CultureInfo class
• Culture string representation based on RFC 1766
  languagecode2-country/regioncode2-script
• Examples en represents neutral English
  en-GB represents UK English
• CultureInfo object
• Invariant absence of culture (may be
  English)
• Neutral en Language NOT specific to
  a particular region
• Specific en-GB Language in a specific
  region, and region info, e.g.,
  formatting

15
Default International behavior

• Default internationalization behavior is
  determined by
• - CurrentCulture and CurrentUICulture
• Determined from either
• CultureInfo class, or the current thread
• Assigned only from the current thread
• CurrentCulture must be a SPECIFIC
  culturedefault culture for System.Globalization
  affects culture specific formatting (date/time,
  number,currency, AND display of Calendar
  control)
• CurrentUICulture Can be neutral or specific
  culturedefault culture used by ResourceManager

16
Setting the Culture

• Web.config
• ltglobalization enableClientBasedCulturetrue
  cultureen-GB
  uicultureen /gt
• Or, lt_at_ Page Cultureautoen-GB
  UICultureautoen . gt
• Page
• Automatic (browsers first requested culture)
  with default lt_at_ Page Cultureautoen-GB
  UICultureautoen .
  gt
• Programmatically
• Analyze complete list of browsers culture
  requests
• Based upon setting in the Users Profile

17
Setting the Culture Collation

• SQL Server 2005 Collations
• Two types
• Windows Collations recommended
• Based upon Windows locales attempt to match SQL
  Server 2005 and Windows localesDefault
  Latin1_General
• SQL Collations -- Legacy with prior version of
  SQL Server
• Called very early in the page life cycle -
  before ALL page events - during the
  FrameworkInitialize method
  before controls are created
• Can set culture based upon LCIDinstead of
  Culture Name - useful for
  alternative Sort Orders

18
Set Culture reviewing all culture requests from
the browser

• Matching browsers culture requests
• Automatic method lt_at_ Page
  Cultureauto .only uses browsers FIRST
  request
• Iterate through the browsers requested cultures
• Browsers cultures are listed in Priority order
  (there are actually weight information)
• Strategies
• Find the first valid culture
• Find the first culture that is supported by
  resource code
• Differentiate between Culture and UICulture

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Set Culture reviewing all browser requests
CODE Sample

• Iterate through the browsers requested cultures
  Part 1 of 2 (Sample taken from .NET
  Internationalization book, pp 148-9)
• protected override void InitializeCulture() if
  (Request.UserLanguages ! null
  Request.UserLanguages.GetLength(0) gt
  0) foreach (string userLanguage in
  Request.UserLanguages) CultureInfo
  cultureInfo GetCultureInfo(userLanguage,
  true) if (cultureInfo ! null) Thread
  .CurrentThread.CurrentUICulture
  cultureInfo Thread.CurrentThread.CurrentCultu
  re CultureInfo.CreateSpecificCulture(cultu
  reInfo.Name) break

20
Set Culture reviewing all browser requests
CODE Sample

• Iterate through the browsers requested cultures
  -- Part 2 of 2 (Sample taken from .NET
  Internationalization book, pp 148-9)
• protected virtual CultureInfo GetCultureInfo( st
  ring userLanguage, bool useUserOverride) int
  semiColonIndex userLanguage.IndexOf("") if
  (semiColonIndex ! -1) userLanguage
  userLanguage.Substring(0, semiColonIndex) try
  return new CultureInfo(userLanguage,
  useUserOverride) catch (ArgumentException)
  return null

21
Set Culture Using Culture Information from User
Profile

• User Profile
• Store users preferred culture information in the
  ASP.NET 2.0 Membership/Profile system
• For each page, or using a new base class for
  all pages (Except the Logon-on pages)
• See Core Internet Application Development with
  ASP.NET 2.0 page 971

22
Respond to the Users preferred culture

• Resource Code
• Formatting

23
Resource Code
24
Setting the Culture - Page

• InitializeCulture method for a page
• Method is new to ASP.NET 2.0
• Called very early in the page life cycle -
  before ALL page events - during the
  FrameworkInitialize method before
  controls are created
• Can set culture based upon LCIDinstead of
  Culture Name - useful for alternative Sort
  Orders

25
Resource code Managers

• ASP.NET Built-in System.Resources.ResourceM
  anager
• Uses standard .resx format
• Easily handled by localization firms
• Directly supported in VS 2005
• Built-in tool to generate .resx filesfrom
  non-localized ASP.NET project
• Cached good performance
• Custom resource managers
• Directly use SQL Server
• Slower performance

26
Creating Resource Files VS 2005 Tool

• Visual Studio 2005 tool Generate
  Local Resources
• Generates resource file for a particular page
  -- from Design view Tools gt Generate Local
  Resoruces
• Automatically creates .resx file that includes
  all properties marked Localizable(true)
• By default, most Webcontrols Text, Title,
  ToolTip
• NOT HTLM controls, except HtmlAnchor, HtmlImage
  
  HtmlInputImage, HtmlTitle
• Automatically modifies the page source
• Does NOT work with raw HTLM, e.g. ltpgttextlt/pgt
  can substitute Localize control

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Resource File Hierarchy

• The Generate Local Resource tool only creates the
  default page resource files.You must copy the
  default resource files and rename then to create
  the language resource hierarchy.

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Generate Local Resources

• Generate Local Resources Example code BEFORE
  using tool lt_at_ Page Language"C"
  AutoEventWireup"true CodeFile"Default.aspx.cs"
  Inherits"_Default" gt
• lttablegt
• lttrgt
• lttd style"width 100px"gt
• ltaspLabel ID"Label1" runat"server"
• Text"User name"gtlt/aspLabelgtlt/tdgt
• lttd style"width 100px"gt
• ltaspTextBox ID"TextBox1" runat"server"gt
• lt/aspTextBoxgtlt/tdgt
• lt/trgt
• lt/tablegt

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Generate Local Resources

• Generate Local Resources Page SourceExample
  code, before using tool
• lt_at_ Page Language"C" AutoEventWireup"true
  CodeFile"Default.aspx.cs" Inherits"_Default" gt
• after using tool
• lt_at_ Page Language"C" AutoEventWireup"true"
• CodeFile"Default.aspx.cs" Inherits"_Default"
• Culture"auto" metaresourcekey"PageResource1"
  UICulture"auto" gt

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Generate Local Resources

• Generate Local Resources Example code, after
  using tool
• lttablegt lttrgt
• lttd style"width 100px"gt
• ltaspLabel ID"Label1" runat"server"
• Text"User Name"
• metaresourcekey"Label1Resource1"gt
• lt/aspLabelgtlt/tdgt
• lttd style"width 100px"gt
• ltaspTextBox ID"TextBox1" runat"server"
• metaresourcekey"TextBox1Resource1"gt
• lt/aspTextBoxgtlt/tdgt
• lt/trgt lt/tablegt

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Resource Code GenerationDemo
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Generate Local Resources

• Generate Local Resources Example Resource file
  

33
Generate Local Resources

• Generate Local Resources
• Original TEXT attribute is retained
• Not used at Runtime
• Shown at design time
• Property Windows - shown with pink icon

34
Preventing localization

• When using the Generate Local Resources tool
• Can prevent a control from being included in
  Generate Local ResourcesltaspLabel ID"Label1"
  runat"server"
• Metalocalizefalse Text"User name"gt
• lt/aspLabelgt

35
Localize control

• Generate Local Resource tool Does NOT work with
  static text, e.g. ltpgtThis is an example.lt/pgt
• Can substitute Localize control (derived from
  Literal), but must contain ONLY static text (no
  ASP.NET controls) ltpgt ltaspLocalize IDlocEx
  runatServergt This is an example.
  lt/aspLocalizegt lt/pgtGenerate Local Resources
  will transform this to ltpgt ltaspLocalize
  IDlocEx runatServergt metaresourcekeylo
  cEx TextThis is an example.gt
  lt/aspLocalizegt lt/pgt

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Explicit Expressions

• Generate Local Resource tool generates IMPLICIT
  expressions for controls with properties marked
  internally as Localizable(true)
• Explicit Expressions useful for binding
  resources to ANY property such as color, or
  ImageURL of ImageControl
• - use in HTML Attributes
• StepsCreate string resource entry
  e.g. WarningColor
• Using Controls Expressions select .
  Select the control, Expression Type choose
  Resources Select the resource entry,
  property, resource

37
Explicit Expressions contd

• Explicit Expressions
• Syntax lt Resources resource-file,
  resource-key gt"
• If resource-file is not specified, then looks
  for resource-key in local resource
• Cannot combine Explicit resource
  expression for a local resource
  and Implicit resource expression within
  same control
• Can combine Explicit resource
  expression for a GLOBAL resource
  and Implicit resource expression within
  same control

38
Global Resources

• Global Resources
• Reduces duplication All pages may share access
  to the same set of resources
• Necessary for Explicit resources where in control
  that also uses Implicit resources
• Compiled into a strongly typed class
• MUST be in folder App_GlobalResources
• MUST use explicit resource references

39
Programmatic Resource Access

• Global Resources
• Can use compiled classname labMessage.Text
  Resources.GlobalColors.WarningColor
• Local Resources
• User the GetLocalResourceObject labMessage.Text
  (string)GetLocalResourceObject(
  PageResources1.title)

40
Formatting
41
Formatting - Overview

• Formatting
• Default setting dictated by CurrentCulture
• Or, you may specify a particular culutre
• Culture senstitive Requires an SPECIFIC Culture
• E.g., en-GBNOT en
• Always use the Globalization class
• Consider Invariant for data exchange

42
Formatting Overview contd

• Formatting
• Implications for
• Text Comparison, case conversion, string length
  Sorting
• Numbers/Currency
• Date/Time
• Issues is the method sensitive to
  CultureInfo.CurrentCulture

43
Text comparison

• String comparison
• Culture Insensitive/Case Insensitive
  (equality operator) String.Equals(String,String)
  
• Culture Sensitive String.Equals(String,String,S
  tringComparison) String.CompareTo(String) Str
  ing.Compare(String,String) String.Compare(String
  ,String,Boolean) case-T/F String.Compare(Strin
  g,String,StringComparison)

44
StringComparison

• StringComparison - Enumeration
• CurrentCulure
• CurrentCultureIgnoreCase
• InvariantCulture
• InvariantCultureIgnoreCase
• Ordinal
• OrdinalIgnoreCase
• Ordinal comparison based upon numerical values
  of the Char objects in each string

45
Case conversion

• Case Conversion
• Many language scripts do not have have a concept
  of case e.g., Japanese, Chinese
• Culture Sensitive String.ToUpper() String.ToUppe
  r(CultureInfo) String.Lower() String.ToLower(Cul
  tureInfo) Char.ToUpper() Char.ToUpper(CultureI
  nfo) Char.ToLower() Char.ToLower(CultureInfo)
• Culture Insensitive
• -- Use CultureInfo overload and specify
• CultureInfo.InvariantCulture

46
Domain Name Processing

• International Domain names
• Originally only 7-bit ASCII characters
• 2003 IETF specifies interim solution until full
  use of Unicode
• Encoding system Unicode to ASCII domain names
• .NET 2.0 idnMapping class idnMapping.GetAsci
  i idnMapping.GetUnicode
• Strategy
• Display (and accept) URLs and e-mail addresses in
  Unicode
• Store and utilize URLs and e-mail addresses in
  Ascii Encoded form

47
Sorting Collation in .NET

• Sorting Issues
• Distinction (CompareOptions enumeration)
• Word sort weights on characters
  e.g., coop sorts close to co-op
• String sort all non-alphanumeric sort before
  alphanumeric
• Ordinal sort based on the numeric value each
  Char object
• Some Unicode characters can have multiple binary
  representations composite characters dual-width
  
• Unicode has four different normalization
  algorithms to normalize a string
• Precise way of sorting/comparison in .NET
• Normalize strings System.String.Normalize -
  used Unicode normalization to map to standard
• Use Ordinal option on Compare to compare strings

48
Sorting/Collation - LCID

• Sorting Issues contd
• Most cultures have multiple sort orders e.g.
  Spanish Modern/International -
  Traditional the culture es-ES uses the
  default Modern/Intl sort
• .NET 2.0 allows creation for alternative
  sorting
• CultureInfo cultureInfo new CultureInfo(es-ES_t
  radnl)
• .NET 1.1 and 2.0 allow using Local ID (LCID)
• CultureInfo cultureInfo new CultureInfo(0x000004
  0A)

49
Numbers/Currency

• Numberic .ToString
• Culture formatted using NumberFormatInfo class
• Can be created for Specific or Invariant
  culture, but NOT created for a neutral
  culture
• Default set by CurrentCultures NumberFormat
  Property
• Standard number format Specifiers
• Uses NumberFormatInfo class
• c, C Currency f, F Fixed Pointn,
  N Number p, P Percent
• Does NOT use NumberFormatInfo class
• d, D Decimal e, E Exponential x,
  X Hexadecimal g, G General r, R Round-trip
• Can specify a particular culture
• Val.ToString(N, new CultureInfo(fr-FR))

50
Numbers/Currency Parsing Input

• Numeric .Parse method
• Uses the CurrentCulture by default
• Can specify a particular culture
• NOTE Formatting characters throw an exception
  UNLESS specify NumberStyles enumeration
• Any all styles except for Hex
• Currency - all styles except for Exponent and
  Hex
• None - all styles except for Exponent and Hex
• Number, Integer
• Example
• CultureInfo MyCultureInfo new
  CultureInfo(en-US)
• String MyString 123,456
• Int MyInt int.Parse(MyString, All,
  MyCultureInfo)

51
DateTime - Output

• DateTime .ToString method
• Culture formatted using DateTimeFormatInfo class
• Can be created for Specific or Invariant
  culture, but NOT created for a neutral
  culture
• Default set by CurrentCultures DateTimeFormat
  Property
• Uses CurrentCulture by default
• ToString() ToShortDateString() ToLongDateString()
  ToShortTimeString() ToLongTimeString()
• Specify particular culture
• ToString(string)
• ToString(string, IFormatProvider)

52
ASP.NET Calendar Control

• ASP.NET Calendar control
• Automatically localized
• Defaults to the CurrentCulture
• NOTE Not CurrentUICulture
• Issue If CurrentCulture and CurrentUICulture
  are different,then the Calendar control will
  appear in the LANGUAGE of the CurrentCulture

53
DateTime Parsing Input

• DateTime.Parse related methods
• .Net Framework 1.1, 2.0 Parse ParseExact
• .Net Framework 2.0 TryParse TryParseExact
• Example CultureInfo MyCultureInfo new
  CultureInfo(de-DE)
• String MyString 12 Juni 2002
• DateTime MyDateTime DateTime.Parse(MyString,
  MyCultureInfo)

54
Suggested References

• Books
• Inside Microsoft SQL Server 2005 The Storage
  Engine pp 11-14 by Kalen Delaney
  ISBN 0735621055
• .NET Internationalization -- by Guy Smith
  Ferrier
  ISBN 0321341384
• Core Internet Application Development with
  ASP.NET 2.0 by Randy Connolly ISBN
  0321419502

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Contact Information Mark Frederiksen Consultant,
ABLE InnovationsPhone [phone]Email
mfrederiksen_at_ableinnovations.com...because
localization doesn't HAVE to be ugly!