Nesting Custom Tags - MACROMEDIA COLDFUSION 5-DEVELOPING Develop Manual

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Nesting Custom Tags

A custom tag can call other custom tags, thereby nesting tags. ColdFusion uses
nested tags such as
and
The calling tag is known as an ancestor, parent, or base tag, while the tags that
ancestor tags call are known as descendant, child, or sub tags. Together, the ancestor
and all descendent tags are called collaborating tags.
The following table lists the terms that describe the relationships between nested
tags:
Calling tag
ancestor
parent
base tag
In order to nest tags, the parent tag must have a closing tag.
You can create multiple levels of nested tags. In this case, the sub tag becomes the
base tag for its own sub tags. Any tag with an end tag present can be an ancestor to
another tag.
Nested custom tags operate through three modes of processing, which are exposed
to the base tags through the variable
Associating sub tags with the base tag
While the ability to create nested custom tags is a tremendous productivity gain,
keeping track of complex nested tag hierarchies can become a chore. The
cfassociate
to a sub tag, you enable communication of its attributes to the base tag.
cfgraph
. The ability to nest tags allows you to provide similar functionality.
cftreeitem
Tag nested within
the calling tag
descendant
child
sub tag
The start mode, in which the base tag is processed for the first time.
The inactive mode, in which sub tags and other code contained within the base
tag are processed. No processing occurs in the base tag during this phase.
The end mode, in which the base tag is processed a second time. The end mode
occurs when ColdFusion reaches the custom tag's end tag.
tag lets the parent know what the children are up to. By adding this tag
and ,
cfgraphdata cfhttp
Description
An ancestor is any tag that contains other tags
between its start and end tags. A descendant is
any tag called by a tag.
Parent and child are synonyms for ancestor
and descendant.
A base tag is an ancestor that you explicitly
associate with a descendant, called a sub tag,
with
cfassociate
thisTag.ExecutionMode
Chapter 10 Reusing Code
and , and
cfhttppam
.
:
cftree