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Chapter 8: Using Flash Remoting for Microsoft .NET
To return a session variable, you use the
Flash.Result
property, as shown in the following
example:
<%@ Page language="c#" debug="true" %>
<%@ Register TagPrefix="Macromedia" Namespace="FlashGateway"
Assembly="flashgateway" %>
<Macromedia:Flash ID="Flash" Runat="Server" />
<%
Flash.Result = session.myPreference;
%>
In the code, the value of the
myPreference
variable is assigned to the
Flash.Result
property,
which is returned to Flash. To set a session variable using a variable passed from Flash Remoting,
you use the
Flash.Params
property, as shown in the following example:
<%@ Page language="c#" debug="true" %>
<%@ Register TagPrefix="Macromedia" Namespace="FlashGateway"
Assembly="flashgateway" %>
<Macromedia:Flash ID="Flash" Runat="Server" />
<%
if (Flash.Params.Count > 0)
{
session.myPreference = Flash.Params[0].ToString();
}
%>
In the code, the parameter passed from Flash is assigned into the
myPreference
session variable.
Using ASP.NET exception handling
To return custom ASP.NET exceptions to Flash, you use the
throw
statement. You can throw
exceptions in the context of a
try
/
catch
statement, an
if
/
else
statement, and so on. For
example, the following C# code fragment throws an exception:
if (Flash.Params.Count == 0)
{
throw new Exception("No arguments received.");
}
In the code, if the
Flash.Params.Count
variable is set to 0, an exception is thrown. The
exception message returns to Flash as part of the
FaultEvent
object. To display the exception in
Flash, you use the
FaultEvent
.
fault.faultstring
property, as shown in the following
ActionScript code fragment:
function serviceFunctionName_Fault (fe:mx.rpc.FaultEvent):Void {
textField = fe.fault.faultstring;
}
In the code, the
fe.fault.faultstring
property is assigned to the textField variable, which
represents a text field in the Flash application. If you want to display the stack trace information
returned from .NET, use the
FaultEvent
.
fault.detail
property. For more information about
the FaultEvent object, see the FaultEvent class in Flash Remoting ActionScript Dictionary Help.
