User Guide

168 Chapter 8: Creating ColdFusion Elements
• Dynamically generate HTML to be returned to the client.
• Set variables within the ColdFusion page from which they are called.
• Throw exceptions that result in standard ColdFusion error messages.
Calling CFX tags
To use a CFX tag, precede the class name with cfx_ and put the name in angle brackets. For
example, use the following line to call the CFX tag defined by the MyCFXClass class and pass it
one attribute.
<cfx_MyCFXClass myArgument="arg1">
Recommended uses
CFX tags provide one way of using C++ or Java code. However, you can also create Java classes
and COM objects and access them using the
cfobject tag. CFX tags, however, provide some
built-in features that the
cfobject tag does not have:
• CFX tags are easier to call in CFML code. You use CFX tags directly in CFML code as you
would any other tag, and you can pass arguments using a standard tag format.
• ColdFusion provides predefined classes for use in your Java or C++ code that facilitate CFX tag
development. These classes include support for request handling, error reporting, and query
management.
You should consider using CFX tags in the following circumstances:
• You already have existing application functionality written in C++ or Java that you want to
incorporate into your ColdFusion application.
• You cannot build the functionality you need using ColdFusion elements.
• You want to provide the new functionality in a tag format, as opposed to using the cfobject
tag to import native Java or COM objects.
• You want use the Java and C++ classes provided by ColdFusion for developing your CFX code.
For more information
For more information on CFX tags, see Chapter 12, “Building Custom CFXAPI Tags,” on
page 259.