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Representation in JavaScript

could be represented by the same code, so the letter

in English could use the same code as a different let-

ter in a different language (obviously, not optimal).

Unicode represents characters as a 16-bit number, allowing for over 65,000 possible characters, making it an

ideal solution to internationalization concerns. Additionally, the first 128 Unicode characters are, in fact, the

128 ASCII characters, making compatibility with older English-language applications much easier.

Representation in JavaScript

All Unicode characters, including ASCII, are represented in Unicode as a four-digit hexadecimal value

prefixed with a

to indicate a Unicode character. For example,

\u0045

is the Unicode form of the

(which can also be represented using ASCII syntax as

\x45

This representation of characters can be used in comments and strings in JavaScript just as you use spe-

cial characters like

. For example:

alert(“\u0048\u0045\u004C\u004C\u004F \u0057\u004F\u0052\u004C\u0044”);

Not sure what this line does? It presents an alert with the text

“HELLO WORLD”

to the user. Using the

Unicode character set, you can create messages in any number of languages. Even though the plain text

form of such messages isn’t human readable, it’s still the only way to deal with multibyte characters

from other languages.

Browser versus operating system support

Just because JavaScript can display and understand Unicode characters doesn’t necessarily mean the

operating system can. Why should this concern Web developers who care only about what the browser

supports, you may ask? The answer is because JavaScript uses some operating system functionality to

do its job, although most developers never realize it. For internationalization, you must be aware of this

very important boundary.

Any time you use

alert()

confirm()

, or

prompt()

, you are using an operating system dialog box.

Unless the client operating system has foreign language support installed, you end up with a dialog full

of gibberish. Most of the time, the browser reflects the language of the operating system, however you

never can tell what individuals with do with their browsers.

When using operating system dialogs with internationalization, be aware that these problems can occur.

When dealing with a distributed Web application, it may be enough to inform the customer of this limi-

tation; on public Web sites, however, it may be best to avoid using these dialogs altogether.

Error-proofing strings

Oftentimes in internationalized Web pages, developers try to pass strings from a server-side variable

into a JavaScript variable using a technique such as this:

<% String sJspHello = “Hello”; %>

var sJavaScriptHello = “<%= sJspHello %>”;

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