702
Chapter 31: Using XML and WDDX
Using WDDX
The following sections describe how you can use WDDX in ColdFusion applications. The first
two sections describe the tools that ColdFusion provides for creating and converting WDDX.
The remaining sections show how you use these tools for common application uses.
Using the cfwddx tag
The
cfwddx
tag can do the following conversions:
A typical
cfwddx
tag used to convert a CFML query object to WDDX looks like the following:
<cfwddx action="cfml2wddx" input="#MyQueryObject#" output="WddxTextVariable">
In this example, MyQueryObject is the name of the query object variable, and WddxTextVariable
is the name of the variable in which to store the resulting WDDX XML. Note
For more information on the
cfwddx
tag, see
CFML Reference
.
Validating WDDX data
The
cfwddx
tag has a
Validate
attribute that you can use when converting WDDX to CFML or
JavaScript. When you set this attribute to True, the XML parser uses the WDDX DTD to
validate the WDDX data before deserializing it. If the WDDX is not valid, ColdFusion generates
an error. By default, ColdFusion does not validate WDDX data before trying to convert it to
ColdFusion or JavaScript data.
The
IsWDDX
function returns True if a variable is a valid WDDX data packet. It returns False
otherwise. You can use this function to validate WDDX packets before converting them to
another format. For example, you can use it instead of the
cfwddx
validate
attribute, so that
invalid WDDX is handled within conditional logic instead of error-handling code. You can also
use it to pre-validate data that will be deserialized by JavaScript at the browser.
Using JavaScript objects
ColdFusion provides two JavaScript objects,
WddxSerializer object
and
WddxRecordset
object
, that you can use in JavaScript to convert data to WDDX. These objects are defined in
the file
webroot
/cfide/scripts/wddx.js.
CFML Reference
describes these objects and their methods in detail. The example
“Transferring
data from the browser to the server” on page 703
shows how you can use these objects to serialize
JavaScript to WDDX.
From
To
CFML
WDDX
CFML
JavaScript
WDDX
CFML
WDDX
JavaScript
Содержание COLDFUSION MX 61-DEVELOPING COLDFUSION MX
Страница 1: ...Developing ColdFusion MX Applications...
Страница 22: ...22 Contents...
Страница 38: ......
Страница 52: ...52 Chapter 2 Elements of CFML...
Страница 162: ......
Страница 218: ...218 Chapter 10 Writing and Calling User Defined Functions...
Страница 250: ...250 Chapter 11 Building and Using ColdFusion Components...
Страница 264: ...264 Chapter 12 Building Custom CFXAPI Tags...
Страница 266: ......
Страница 314: ...314 Chapter 14 Handling Errors...
Страница 344: ...344 Chapter 15 Using Persistent Data and Locking...
Страница 349: ...About user security 349...
Страница 357: ...Security scenarios 357...
Страница 370: ...370 Chapter 16 Securing Applications...
Страница 388: ...388 Chapter 17 Developing Globalized Applications...
Страница 408: ...408 Chapter 18 Debugging and Troubleshooting Applications...
Страница 410: ......
Страница 426: ...426 Chapter 19 Introduction to Databases and SQL...
Страница 476: ...476 Chapter 22 Using Query of Queries...
Страница 534: ...534 Chapter 24 Building a Search Interface...
Страница 556: ...556 Chapter 25 Using Verity Search Expressions...
Страница 558: ......
Страница 582: ...582 Chapter 26 Retrieving and Formatting Data...
Страница 668: ......
Страница 734: ...734 Chapter 32 Using Web Services...
Страница 760: ...760 Chapter 33 Integrating J2EE and Java Elements in CFML Applications...
Страница 786: ...786 Chapter 34 Integrating COM and CORBA Objects in CFML Applications...
Страница 788: ......
Страница 806: ...806 Chapter 35 Sending and Receiving E Mail...