MACROMEDIA COLDFUSION 5-DEVELOPING, Руководство по разработке

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394 Chapter 21 Building Custom CFXAPI Tags
This section provides an overview of these object types. For a complete example Java
CFX that uses
Request
,
Response
, and
Query
objects, see the “ZipBrowser Example”
on page 397.
Request object
The
Request
object is passed to the
processRequest
method of the
CustomTag
interface. It provides methods for retrieving attributes, including queries, passed to
the tag and for reading global tag settings.
Response object
The
Response
object is passed to the
processRequest
method of the
CustomTag
interface. It provides methods for writing output, generating queries, and setting
variables within the calling page.
Query object
The
Query
object provides an interface for working with ColdFusion queries. It
includes methods for retrieving name, row count, and column names and methods
for getting and setting data elements.
Method Description
attributeExists Checks whether the attribute was passed to this tag.
getAttribute Retrieves the value of the passed attribute.
getIntAttribute Retrieves the value of the passed attribute as an integer.
getAttributeList Retrieves a list of all attributes passed to the tag.
getQuery Retrieves the query that was passed to this tag, if any.
getSetting Retrieves the value of a global custom tag setting.
debug Checks whether the tag contains the
debug
attribute.
Method Description
write
Outputs text into the calling page.
setVariable Sets a variable in the calling page.
addQuery Adds a query to the calling page.
writeDebug Outputs text into the debug stream.
Method Description
getName Retrieves the name of the query.
getRowCount
Retrieves the number of rows in the query.
getColumns
Retrieves the names of the query columns.
getData
Retrieves a data element from the query.