Using Flash Remoting MX
Using Flash Remoting Data in ActionScript

Converting from application server data types to ActionScript

Flash Remoting MX automatically converts between the data types specific to the application server programming environment and ActionScript.

The following table shows how Flash Remoting MX converts data returned from the application server to ActionScript data types:

C#	Visual Basic	SOAP	ColdFusion MX	Java	ActionScript
null	Nothing	null	N/A	null	null
bool System.Boolean	Boolean	boolean	Boolean, 0, or 1 For details, see "Boolean data in ColdFusion"	Boolean	Boolean
any number type	any number type	decimal, float, double	Val(Number) For details, see "Numeric data in ColdFusion"	Number	Number
System.Char System.String	Char String	string	String	String Character	String See "Server data conversion notes"
System.DateTime	Date	dateTime	Date	Date	Date
System.Collections.ICollection object[]	System.Collections.ICollection object[]	array	Array	Collection Object[] array of primitive types	Array
System.Collections.Hashtable System.Collections.IDictionary	System.Collections.Hashtable System.Collections.IDictionary	complex type	Struct	java.util.Map	Associative array
Sytem.Data. DataSet	Sytem.Data. DataSet	Complex type (DataSet)	-	-	Associative array of RecordSet objects
System.Data.Data Table	System.Data.Data Table	-	Query object	java.sql.Result Set	RecordSet
-	-	-	Query object (Flash.pagesize variable set)	flashgateway. sql.Pageable ResultSet	Paged RecordSet
FlashGateway.IO. ASObject System.Exception	FlashGateway.IO. ASObject System.Exception	Complex type	A Java object as listed in the next column	flashgateway.io. ASObject Serializable Dictionary Throwable	Object
FlashGateway.IO. ASObject with Type property set	FlashGateway.IO. ASObject with Type property set	Complex type	Java Object of class flashgateway.io. ASObject with Type property set (Set the type using a Java expression once you create the object using CFML.)	flashgateway.io. ASObject with Type property set	Typed Object See "Server data conversion notes"
System.Xml. XmlDocument	System.Xml. XmlDocument	-	XML	org.w3c.dom. Document flashgateway.io.ASXMLString	XML

Server data conversion notes

The following is additional information on conversion from server data types to ActionScript data types:

• If a string data type on the server represents a valid number in ActionScript, Flash can automatically cast it to a number if needed.
• If you use the setType method to assign an object type to a flashgateway.io.ASObject object on the server, and the type name matches the name of a registered class in ActionScript, Flash Remoting MX creates an instance of that type in ActionScript. For more information see "Working with ActionScript typed objects".
• To return multiple, independent, values to your Flash application, place them in a complex server variable that can hold all the required data, such as a variable that converts to a Flash Object, Array, or Associative Array type. Return the single variable and use its elements in the Flash application.

ColdFusion to ActionScript data conversion issues

ColdFusion is a loosely typed or "untyped" language, where the data type of a variable can be ambiguous. As a result, Flash Remoting MX cannot always determine how to convert between ColdFusion data and ActionScript data. The following sections discuss the limitations that this situation imposes, and how to prevent errors that can arise as a result.

Boolean data in ColdFusion

If a ColdFusion page or CFC returns Boolean values, it represents these values as strings. Flash does not have rules for converting strings to Boolean values. Instead, it converts the string to a number, and then converts the number to a Boolean value. This operation converts all representations of Boolean values to False. Therefore Flash converts ColdFusion Boolean values of "Yes", "True", and True to False.

To return a Boolean value correctly from ColdFusion to ActionScript, do either of the following:

• Return a 1 (True) or 0 (False) numeric or string value. For example, the following function converts any ColdFusion Boolean value to value that ActionScript can use correctly. (For simplicity, this example omits error-handling code.) Your ColdFusion page can call this function before returning a Boolean value to Flash Remoting MX:

  <cffunction name="convertBool">
    <cfif Arguments[1] >
      <cfreturn "1">
    <cfelse>
      <cfreturn "0">
    </cfif>
  </cffunction>
  

• Specify the returnType="boolean" attribute in the cffunction tag, as in the following example. When a Flash application calls this ColdFusion function as a service, the function returns a valid Boolean True value to Flash.

  <cffunction name="getBool" access="remote" returntype="boolean">
    <cfset foo = True> 
      <cfreturn foo>
  </cffunction>
  

Numeric data in ColdFusion

If a ColdFusion page or CFC returns a numeric value without specifically identifying the value as numeric, Flash Remoting MX treats the value as a string when passing it to the responder. For example, if you have the following user-defined function and ActionScript code, Flash displays 22, not 4, in the trace message:

ColdFusion:

<cffunction name="getNumber"access="remote">

  <cfreturn 2>
</cffunction>

ActionScript:

function getNumber_Result ( result )
{ 

  myVar = (result + 2);
  trace (myVar);
}

To prevent such problems, do either of the following:

• Specify the returnType="numeric" attribute in the cffunction tag, as in the following example:

  <cffunction name="getNumber" access="remote" returnType="numeric">
    <cfset foo = 2> 
      <cfreturn foo>
  </cffunction>
  

• Use the Val function to explicitly convert the value to a number before you return it, as in the following example:

  <cffunction name="getNumber" access="remote">
    <cfset foo = Val(2)> 
      <cfreturn foo>
  </cffunction>
  

If you call either of these getNumber functions from Flash, the ActionScript getNumber_Result function displays the value 4.

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