MACROMEDIA COLDFUSION MX 61-CFML, Reference

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Scope-specific built-in variables 23
Scope-specific built-in variables
ColdFusion returns variables, such as those returned in a
cfdirectory
or
cfftp
operation. A
variable is usually referenced by scoping it according to its type: naming it according to the code
context in which it is available; for example, Session.varname, or Application.varname. For more
information on ColdFusion scopes, see Chapter 3, “Using ColdFusion Variables,” in
Developing
ColdFusion MX Applications
You use the
cflock
tag to limit the scope of CFML constructs that modify shared data structures,
files, and CFXs, to ensure that modifications occur sequentially. For more information, see
cflock
on page 221 , and Chapter 15, “Using Persistent Data and Locking,” in Developing
ColdFusion MX Applications
.
Variable scope
ColdFusion supports the Variables scope. Unscoped variables created with the
cfset
tag acquire
the Variables scope by default. For example, the variable created by the statement
<CFSET
linguist = Chomsky>
can be referenced as
#Variables.linguist#
Caller scope
History
ColdFusion MX: The Caller scope is accessible as a structure. (In earlier releases, it was not.)
Client variables
The following client variables are read-only:
Client.CFID
Client.CFToken
Client.HitCount
Client.LastVisit
Client.TimeCreated
Client.URLToken
Server variables
Use the Server prefix to reference server variables, as follows:
Server.ColdFusion.ProductName
Server.ColdFusion.ProductVersion
Server.ColdFusion.ProductLevel
Server.ColdFusion.SerialNumber
Server.ColdFusion.SupportedLocales
Server.OS.Name
Server.OS.AdditionalInformation
Server.OS.Version
Server.OS.BuildNumber
Application and session variables
To enable application and session variables, use the
cfapplication
tag. Reference them as
follows:
Application. myvariable
Session. myvariable