MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX Develop Manual page 384

Handling URL strings
URL requests to a server often contain name/value pairs as part of the request. For example, the
following URL contains name/value pairs as part of the URL:
http://company.com/prod_page.cfm?name=Stephen;ID=7645
As discussed previously, URL characters entered using any character encoding other than US-
ASCII are URL-encoded in a hexadecimal format. However, by default, a web server assumes that
the characters of a URL string are single-byte characters.
One common method used to support non-ASCII characters within a URL is to include a name/
value pair within the URL that defines the character encoding of the URL. For example, the
following URL uses a parameter called encoding to define the character encoding of the URL
parameters:
http://company.com/prod_page.cfm?name=Stephen;ID=7645;encoding=Latin-1
Within the prod_page.cfm page, you can check the value of the encoding parameter before
processing any of the other name/value pairs. This guarantees that you will handle the parameters
correctly.
You can also use the
The
SetEncoding
second specifies the character encoding used by the scope. Since ColdFusion writes URL
parameters to the URL scope, you specify "URL" as the scope parameter to the function.
For example, if the URL parameters were passed using Shift-JIS, you could access them as follows:
<cfscript>
setEncoding("URL", "Shift_JIS");
writeoutput(URL.name);
writeoutput(URL.ID);
</cfscript>
Note: To specify the Shift-JIS character encoding, use the Shift_JIS attribute, with an underscore (_),
not a hyphen (-).
Handling form data
The HTML
form
that text to the server. The form tags are designed to work only with single-byte character data.
Since ColdFusion uses two bytes per character when it stores strings, ColdFusion converts each
byte of the form input into a two-byte representation.
However, if a user enters double-byte text into the form, the form interprets each byte as a single
character, rather than recognize that each character is two bytes. This will corrupt the input text,
as the following example shows:
A customer enters three double-byte characters in a form, represented by six bytes.
1
The form returns the six bytes to ColdFusion as six characters. ColdFusion converts them to a
2
representation using two bytes per input byte for a total of twelve bytes.
Outputting these characters results in corrupt information displayed to the user.
3
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function to specify the character encoding of URL parameters.
SetEncoding
function takes two parameters: the first specifies a variable scope and the
tag and the ColdFusion tag let users enter text on a page, then submit
cfform