Conversion Module

This XQuery Module contains functions to convert data between different formats.

Conventions

All functions in this module are assigned to the http://basex.org/modules/convert namespace, which is statically bound to the convert prefix.
All errors are assigned to the http://basex.org/errors namespace, which is statically bound to the bxerr prefix.

Strings

convert:binary-to-string

Signatures	convert:binary-to-string($bytes as basex:binary) as xs:string convert:binary-to-string($bytes as basex:binary, $encoding as xs:string) as xs:string
Summary	Converts the specifed binary data (xs:base64Binary, xs:hexBinary) to a string. The UTF-8 default encoding can be overwritten with the optional $encoding argument.
Errors	BXCO0001: The input is an invalid XML string, or the wrong encoding has been specified. BXCO0002: The specified encoding is invalid or not supported.
Examples	convert:binary-to-string(xs:hexBinary('48656c6c6f576f726c64')) returns the string HelloWorld.

convert:string-to-base64

Signatures	convert:string-to-base64($input as xs:string) as xs:base64Binary convert:string-to-base64($input as xs:string, $encoding as xs:string) as xs:base64Binary
Summary	Converts the specified string to a xs:base64Binary item. If the default encoding is chosen, conversion will be cheap, as both xs:string and xs:base64Binary items are internally represented as byte arrays. The UTF-8 default encoding can be overwritten with the optional $encoding argument.
Errors	BXCO0001: The input cannot be represented in the specified encoding. BXCO0002: The specified encoding is invalid or not supported.
Examples	convert:string-to-base64('HelloWorld') returns the xs:base64binary item SGVsbG9Xb3JsZA==.

convert:string-to-hex

Signatures	convert:string-to-hex($input as xs:string) as xs:hexBinary convert:string-to-hex($input as xs:string, $encoding as xs:string) as xs:hexBinary
Summary	Converts the specified string to a xs:hexBinary item. If the default encoding is chosen, conversion will be cheap, as both xs:string and xs:hexBinary items are internally represented as byte arrays. The UTF-8 default encoding can be overwritten with the optional $encoding argument.
Errors	BXCO0001: The input cannot be represented in the specified encoding. BXCO0002: The specified encoding is invalid or not supported.
Examples	convert:string-to-hex('HelloWorld') returns the Base64 item 48656C6C6F576F726C64.

Byte Arrays

convert:bytes-to-base64

Signatures	convert:bytes-to-base64($input as xs:byte*) as xs:base64Binary
Summary	Converts the specified byte sequence to a xs:base64Binary item. Conversion is cheap, as xs:base64Binary items are internally represented as byte arrays.
Errors	BXCO0001: The input cannot be represented in the specified encoding. BXCO0002: The specified encoding is invalid or not supported.
Examples	convert:string-to-base64('HelloWorld') returns the xs:base64binary item SGVsbG9Xb3JsZA==.

convert:bytes-to-hex

Signatures	convert:string-to-hex($input as xs:byte*) as xs:hexBinary
Summary	Converts the specified byte sequence to a xs:hexBinary item. Conversion is cheap, as xs:hexBinary items are internally represented as byte arrays.
Errors	BXCO0001: The input cannot be represented in the specified encoding. BXCO0002: The specified encoding is invalid or not supported.
Examples	convert:string-to-hex('HelloWorld') returns the Base64 item 48656C6C6F576F726C64.

convert:binary-to-bytes

Signatures	convert:binary-to-bytes($bin as basex:binary) as xs:byte*
Summary	Returns the specified binary data (xs:base64Binary, xs:hexBinary) as a sequence of bytes.
Examples	convert:binary-to-bytes(xs:base64Binary('QmFzZVggaXMgY29vbA==')) returns the sequence (66, 97, 115, 101, 88, 32, 105, 115, 32, 99, 111, 111, 108). convert:binary-to-bytes(xs:hexBinary("4261736558")) returns the sequence (66 97 115 101 88).

Numbers

convert:integer-to-base

Signatures	convert:integer-to-base($num as xs:integer, $base as xs:integer) as xs:string
Summary	Converts $num to base $base, interpreting it as a 64-bit unsigned integer. The first $base elements of the sequence '0',..,'9','a',..,'z' are used as digits. Valid bases are 2, .., 36.
Examples	convert:integer-to-base(-1, 16) returns the hexadecimal string 'ffffffffffffffff'. convert:integer-to-base(22, 5) returns '42'.

convert:integer-from-base

Signatures	convert:integer-from-base($str as xs:string, $base as xs:integer) as xs:integer
Summary	Decodes an xs:integer from $str, assuming that it's encoded in base $base. The first $base elements of the sequence '0',..,'9','a',..,'z' are allowed as digits, case doesn't matter. Valid bases are 2 - 36. If $str contains more than 64 bits of information, the result is truncated arbitarily.
Examples	convert:integer-from-base('ffffffffffffffff', 16) returns -1. convert:integer-from-base('CAFEBABE', 16) returns 3405691582. convert:integer-from-base('42', 5) returns 22. convert:integer-from-base(convert:integer-to-base(123, 7), 7) returns 123.

Dates

convert:ms-to-dateTime

Signatures	convert:ms-to-dateTime($number as xs:integer) as xs:dateTime
Summary	Converts the specified $number of milliseconds since 1 Jan 1970 to a dateTime item.
Examples	convert:ms-to-dateTime(0) returns 1970-01-01T00:00:00Z. convert:ms-to-dateTime(1234567890123) returns 2009-02-14T00:31:30.123Z.

convert:dateTime-to-ms

Signatures	convert:dateTime-to-ms($dateTime as xs:dateTime) as xs:integer
Summary	Converts the specified $dateTime to number of milliseconds since 1 Jan 1970.
Examples	convert:dateTime-to-ms(xs:dateTime('1970-01-01T00:00:00Z')) returns 0.

Errors

Code	Description
BXCO0001	The input is an invalid XML string, or the wrong encoding has been specified.
BXCO0002	The specified encoding is invalid or not supported.

Changelog

Version 7.4

• Added: convert:ms-to-dateTime, convert:dateTime-to-ms

The module was introduced with Version 7.3. Some of the functions have been adopted from the obsolete Utility Module.