MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX Develop Manual page 700

WDDX data type support
The following sections describe the data types that WDDX supports. This information is a
distillation of the description in the WDDX DTD. For more detailed information, see the DTD
at www.openwddx.org.
Basic data types
WDDX can represent the following basic data types:
Data type
Null
Numbers
Date-time values
Strings
Complex data types
WDDX can represent the following complex data types:
Data type Description
Array Arrays are integer-indexed collections of objects of arbitrary type. Because most
languages start array indexes at 0, while CFML array indexes start at 1, working with
array indices can lead to nonportable data.
Structure Structures are string-indexed collections of objects of arbitrary type, sometimes
called associative arrays. Because some of the languages supported by WDDX are
not case-sensitive, no two variable names in a structure can differ only in their case.
Recordset Recordsets are tabular rows of named fields, corresponding to ColdFusion query
objects. Only simple data types can be stored in recordsets. Because some of the
languages supported by WDDX are not case-sensitive, no two field names in a
recordset can differ only in their case. Field names must satisfy the regular
expression [_A-Za-z][_.0-9A-Za-z]* where the period (.) stands for a literal period
character, not "any character".
Binary The binary data type represents strings (blobs) of binary data. The data is encoded in
MIME base64 format.
700 Chapter 31: Using XML and WDDX
Description
Null values in WDDX are not associated with a type such as number or
string. The cfwddx tag converts WDDX Nulls to empty strings.
WDDX documents use floating point numbers to represent all numbers. The
range of numbers is restricted to +/-1.7E+/-308. The precision is restricted
to 15 digits after the decimal point.
Date-time values are encoded according to the full form of ISO8601; for
example, 2002-9-15T09:05:32+4:0.
Strings can be of arbitrary length and must not contain embedded nulls.
Strings can be encoded using double-byte characters.