MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Develop Manual

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Building ColdFusion components 241
In this case, a ColdFusion page with the following code sets the MetaTypeInfo variable to Float:
<cfobject component="mathCFC" name="MathFuncs">
<cfset MetaTypeInfo=GetMetadata(MathFuncs).MetaType>
Note: Avoid using expressions in custom metadata attributes. Using expressions in metadata
attributes can cause unpredictable behavior, because all metadata expressions are replaced by
strings in the metadata structure returned from the GetMetadata function. Also, do not use the
reserved attributes as your metadata attribute names. The reserved words for the
cfcomponent
tag are
name, path, properties, functions, and extends. The reserved words for the
cffunction
tag are name,
returnType, access, roles, output, and arguments. The reserved words for the
cfargument
tag are
name, required, default, and type. The reserved words for the
cfproperty
tag are name and type.
The cfproperty tag
The
cfproperty
tag has several purposes:
•
It can create complex data types with WSDL descriptions for ColdFusion web services. For
more information, see
“Using ColdFusion components to define data types for web services”
on page 724 of Chapter 32, Using Web Services .
•
It can provide documentation of component properties in the ColdFusion introspection
output. The introspection information includes the values of the standard
cfproperty
tag
attributes.
Note: The
cfproperty
tag does not create a variable or assign it a value. It is used for information
purposes only. You use a cfset tag, or CFScript assignment statement to create the property and
set its value.
Saving and naming ColdFusion components
The following table lists the locations in which you can save component files and how they can be
accessed from each location:
Note: ColdFusion MX mappings and custom tag roots can exist within the web root. If so, they are
accessible to remote requests, including URL, form, Flash Remoting, and web service invocation.
Your application can refer to any component in one of these directories specifically by using a
qualified component name that starts with a subdirectory of one of the accessible directories and
uses a period to delimit each directory in the path to the directory that contains the component.
For example, the following example is a qualified name of a saw component:
com.mycompany.catalog.product.saw
In this example, the saw.cfc file must be in the com\mycompany\catalog\product subdirectory of
a directory that ColdFusion searches for components, as listed in the preceding table. When you
refer to a component using the qualified name, ColdFusion looks for the component in the order
described in
“Specifying the CFC location” on page 224 .
Web root
ColdFusion
mappings
Custom
tag roots
Current
directory
URL
Yes No No N/A
Form
Yes No No Yes
Flash Remoting
Yes No No N/A
Web services
Yes No No N/A
ColdFusion page
Yes Yes Yes Yes