Adobe COLDFUSION 9 Manual page 50

DEVELOPING COLDFUSION 9 APPLICATIONS
The CFML Programming Language
How ColdFusion stores dates and times
ColdFusion stores and manipulates dates and times as date-time objects. Date-time objects store data on a timeline as
real numbers. This storage method increases processing efficiency and directly mimics the method used by many
database systems. In date-time objects, one day is equal to the difference between two successive integers. The time
portion of the date-and-time value is stored in the fractional part of the real number. The value 0 represents 12:00 AM
12/30/1899.
Although you can use arithmetic operations to manipulate date-and-time values directly, this method can result in
code that is difficult to understand and maintain. Use the ColdFusion date-time manipulation functions instead. For
information on these functions, see the CFML Reference.
Binary data type and binary encoding
Binary data (also referred to as a binary object) is raw data, such as the contents of a GIF file or an executable program
file. You do not normally use binary data directly, but you can use the
typically for conversion to a string binary encoding before transmitting the file using e-mail.
A string binary encoding represents a binary value in a string format that can be transmitted over the web. ColdFusion
supports three binary encoding formats:
Encoding Format
Base64 Encodes the binary data in the lowest six bits of each byte. It ensures that binary data and non-ANSI character data
can be transmitted using e-mail without corruption. The Base64 algorithm is specified by IETF RFC 2045, at
www.ietf.org/rfc/rfc2045.txt.
Hex Uses two characters in the range 0-9 and A-F represent the hexadecimal value of each byte; for example, 3A.
UU Uses the UNIX UUencode algorithm to convert the data.
ColdFusion provides the following functions that convert among string data, binary data, and string encoded binary
data:
Function Description
BinaryDecode Converts a string that contains encoded binary data to a binary object.
BinaryEncode Converts binary data to an encoded string.
CharsetDecode Converts a string to binary data in a specified character encoding.
CharsetEncode Converts a binary object to a string in a specified character encoding.
ToBase64 Converts string and binary data to Base64 encoded data.
ToBinary Converts Base64 encoded data to binary data. The BinaryDecode function provides a superset of the ToBase64
functionality.
ToString Converts most simple data types to string data. It can convert numbers, date-time objects, and Boolean values. (It
converts date-time objects to ODBC timestamp strings.) Adobe recommends that you use the CharsetEncode
function to convert binary data to a string in new applications.
Complex data types
Arrays, structures, and queries are ColdFusion built-in complex data types. Structures and queries are sometimes
referred to as objects, because they are containers for data, not individual data values.
For details on using arrays and structures, see
cffile
"Using Arrays and Structures" on page 82.
Last updated 8/5/2010
tag to read a binary file into a variable,
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