MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Develop Manual

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Using the Flash Remoting service with ColdFusion pages 645
In this example, the query results are filtered by the value of
Flash.paramName
, which references
the first parameter in the array. If the parameters were passed as an ordered array from Flash, you
use standard structure name syntax; for example:
<cfset flash.result = "Variable 1:#Flash.params[1]#, Variable 2:
#Flash.params[2]#">
In this ActionScript example, notice that ActionScript starts the array index at zero. ColdFusion
array indexes start at one.
Returning results to Flash
In ColdFusion pages, only the value of
Flash.Result
variable is returned to the Flash
application. For more information about supported data types between ColdFusion and Flash, see
the data type table in
“Using the Flash Remoting service with ColdFusion pages” on page 643 .
The following procedure creates the service function
helloWorld
, which returns a structure
containing simple messages to the Flash application.
To create a ColdFusion page that passes a structure to Flash:
1
Create a folder in your web root, and name it helloExamples.
2
Create a ColdFusion page, and save it as helloWorld.cfm in the helloExamples directory.
3
Modify helloWorld.cfm so that the CFML code appears as follows:
<cfset tempStruct = StructNew()>
<cfset tempStruct.timeVar = DateFormat(Now ())>
<cfset tempStruct.helloMessage = "Hello World">
4
In the example, two string variables are added to a structure, one with a formatted date and one
with a simple message. The structure is passed back to the Flash application using the
Flash.Result
variable.
5
Save the file.
Remember, the directory name is used the service address, and the helloWorld.cfm file is a
method of the
helloExamples
Flash Remoting service. The following ActionScript example calls
the helloWorld ColdFusion page:
include "NetServices.as"
NetServices.setDefaultGatewayUrl("http://localhost:8500/flashservices/
gateway");
gatewayConnection = NetServices.createGatewayConnection();
CFMService = gatewayConnection.getService(
"helloExamples", this);
CFMService.helloWorld();
Note: Due to ActionScript's automatic type conversion, do not return a boolean literal to Flash from
ColdFusion. Return
1
to indicate true, and return
0
to indicate false.
Returning records in increments to Flash
ColdFusion lets you return record set results to Flash in increments. For example, if a query
returns 20 records, you can set the
Flash.Pagesize
variable to return five records at a time to
Flash. Incremental record sets lets you minimize the time that Flash application waits for the
application server data to load.