PARSE XML
operand1
[INTO [PATH
operand2]
[NAME
operand3]
[VALUE
operand4]]
|
|
[[NORMALIZE ]
NAMESPACE
operand5
PREFIX
operand6]
|
|
statement... | |
END-PARSE
|
(structured mode only) |
LOOP |
(reporting mode only) |
This document covers the following topics:
For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.
Related Statement: REQUEST
DOCUMENT
Belongs to Function Group: Internet and Parsing
The PARSE XML
statement allows you to parse XML documents from a Natural
program. See also Statements for Internet Access
and Parsing in the Programming Guide.
It is recommended that you use dynamic variables when using the PARSE XML
statement, because it is impossible to determine the length of a static variable. Using
static variables could in turn lead to the truncation of the value that is to be written
into the variable.
For information on Unicode support, see PARSE
XML
in the Unicode and Code Page Support
documentation.
The following are markings used in path strings to represent the different data types in an XML document (on ASCII-based systems):
Marking | XML Data | Location in Path String |
---|---|---|
? |
Processing instruction (except for <?XML...?> )
|
end |
! |
Comment | end |
C |
CDATA section | end |
@ |
Attribute (on mainframes: § or @, depending on session code page and terminal emulation) | before the attribute name |
/ |
Closing tag and/or parent name separator in a path | end or between parent names |
$ |
Parsed data - character data string | end |
By using this additional markup in the path string, one can more easily identify the different elements of the XML document in the output document.
To specify the global namespace, use a colon (:) as prefix and an empty URI.
The following Natural system variables are automatically created for each PARSE
XML
statement issued:
The notation
(r)
after
*PARSE-TYPE
, *PARSE-LEVEL
,
*PARSE-ROW
, *PARSE-COL
and
*PARSE-NAMESPACE-URI
is used to indicate the label or
statement number of the statement in which the PARSE
was issued. If
(r)
is not specified, the corresponding
system variable represents the system variable of the XML data currently being processed
in the active PARSE
processing loop.
For more information on these system variables, see the System Variables documentation.
Operand Definition Table:
Operand | Possible Structure | Possible Formats | Referencing Permitted | Dynamic Definition | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
operand1
|
C | S | A | U | B | yes | no | |||||||||||||
operand2
|
S | A | U | B | yes | yes | ||||||||||||||
operand3
|
S | A | U | B | yes | yes | ||||||||||||||
operand4
|
S | A | U | B | yes | yes | ||||||||||||||
operand5
|
S | A | A | U | B | yes | yes | |||||||||||||
operand6
|
S | A | A | U | B | yes | yes |
Syntax Element Description:
Syntax Element | Description |
---|---|
operand1
|
XML
Document: operand1
represents the XML document in question. The XML document may not be changed while
it is being parsed. If you try to change the XML document during parsing (by
writing into it, for example), an error message will be displayed.
|
PATH operand2
|
Path:
The Note: See also Example 1 - Using the PATH Option. |
NAME operand3
|
Data Element Name:
If See also Example 2 - Using the NAME Option. |
VALUE operand4
|
Data Element Content:
If there is no value, a given dynamic variable will be set to
See also Example 3 - Using the VALUE Option. |
operand5 and
operand6
|
Namespace URI and Prefix:
The
Namespace normalization is a feature of the <myns:myentity xmlns:myns="http://myuri" /> The
The namespace With namespace normalization, all namespace The uri(1) := 'http://namespaces.softwareag.com/natural/demo' pre(1) := 'nat:' If See also: Additional Information Concerning PREFIX:
In addition, the following applies to the prefix definition:
|
END-PARSE |
End of PARSE XML Statement:
In structured mode, the Natural reserved keyword In reporting mode, the Natural statement |
LOOP |
The following code:
** Example 'PAXMLEX1': PARSE XML (with PATH and CODEPAGE) ** ** Note: Natural session parameter XML has to be set at least: ** XML=(ON,PARSE=ON). ************************************************************************ DEFINE DATA LOCAL 1 MYXML (A) DYNAMIC 1 MYPATH (A) DYNAMIC END-DEFINE * COMPRESS '<?xml version="1.0" ?>' '<employee personnel-id="30016315" >' '<full-name>' '<!--this is just a comment-->' '<first-name>RICHARD</first-name>' '<name>FORDHAM</name>' '</full-name>' '</employee>' INTO MYXML LEAVING NO * PARSE XML MYXML INTO PATH MYPATH PRINT MYPATH END-PARSE END
produces the following output:
employee employee/@personnel-id employee/full-name employee/full-name/! employee/full-name/first-name employee/full-name/first-name/$ employee/full-name/first-name// employee/full-name/name employee/full-name/name/$ employee/full-name/name// employee/full-name// employee//
The following code:
** Example 'PAXMLEX2': PARSE XML (with PATH and NAME) ** ** Note: Natural session parameter XML has to be set at least: ** XML=(ON,PARSE=ON). ************************************************************************ DEFINE DATA LOCAL 1 MYXML (A) DYNAMIC 1 MYPATH (A) DYNAMIC 1 MYNAME (A) DYNAMIC END-DEFINE * COMPRESS '<?xml version="1.0" ?>' '<employee personnel-id="30016315" >' '<full-name>' '<!--this is just a comment-->' '<first-name>RICHARD</first-name>' '<name>FORDHAM</name>' '</full-name>' '</employee>' INTO MYXML LEAVING NO * PARSE XML MYXML INTO PATH MYPATH NAME MYNAME DISPLAY (AL=39) MYPATH MYNAME END-PARSE END
produces the following output:
MYPATH MYNAME ---------------------------------- ----------------------------------- employee employee employee/@personnel-id personnel-id employee/full-name full-name employee/full-name/! employee/full-name/first-name first-name employee/full-name/first-name/$ employee/full-name/first-name// first-name employee/full-name/name name employee/full-name/name/$ employee/full-name/name// name employee/full-name// full-name employee// employee
The following code:
** Example 'PAXMLEX3': PARSE XML (with PATH and VALUE) ** ** Note: Natural session parameter XML has to be set at least: ** XML=(ON,PARSE=ON). ************************************************************************ DEFINE DATA LOCAL 1 MYXML (A) DYNAMIC 1 MYPATH (A) DYNAMIC 1 MYVALUE (A) DYNAMIC END-DEFINE * COMPRESS '<?xml version="1.0" ?>' '<employee personnel-id="30016315" >' '<full-name>' '<!--this is just a comment-->' '<first-name>RICHARD</first-name>' '<name>FORDHAM</name>' '</full-name>' '</employee>' INTO MYXML LEAVING NO * PARSE XML MYXML INTO PATH MYPATH VALUE MYVALUE DISPLAY (AL=39) MYPATH MYVALUE END-PARSE END
produces the following output:
MYPATH MYVALUE ---------------------------------- ----------------------------------- employee employee/@personnel-id 30016315 employee/full-name employee/full-name/! this is just a comment employee/full-name/first-name employee/full-name/first-name/$ RICHARD employee/full-name/first-name// employee/full-name/name employee/full-name/name/$ FORDHAM employee/full-name/name// employee/full-name// employee//
The following XML code:
myxml := '<?xml version="1.0" ?>'- '<nat:employee nat:personnel-id="30016315"'- ' xmlns:nat="http://namespaces.softwareag.com/natural/demo">'- '<nat:full-Name>'- '<nat:first-name>RICHARD</nat:first-name>'- '<nat:name>FORDHAM</nat:name>'- '</nat:full-Name>'- '</nat:employee>'
processed by the following Natural code:
PARSE XML myxml INTO PATH mypath PRINT mypath END-PARSE
produces the following output:
nat:employee nat:employee/@nat:personnel-id nat:employee/@xmlns:nat nat:employee/nat:full-Name nat:employee/nat:full-Name/nat:first-name nat:employee/nat:full-Name/nat:first-name/$ nat:employee/nat:full-Name/nat:first-name// nat:employee/nat:full-Name/nat:name nat:employee/nat:full-Name/nat:name/$ nat:employee/nat:full-Name/nat:name// nat:employee/nat:full-Name// nat:employee//
Using NORMALIZE NAMESPACE
, the
same XML document as in Example 4 with a different NAMESPACE PREFIX
produces the same output.
XML code:
myxml := '<?xml version="1.0" ?>'- '<natural:employee natural:personnel-id="30016315"'- ' xmlns:natural="http://namespaces.softwareag.com/natural/demo">'- '<natural:full-Name>'- '<natural:first-name>RICHARD</natural:first-name>'- '<natural:name>FORDHAM</natural:name>'- '</natural:full-Name>'- '</natural:employee>'
Natural code:
uri(1) := 'http://namespaces.softwareag.com/natural/demo' pre(1) := 'nat:' * PARSE XML myxml INTO PATH mypath NORMALIZE NAMESPACE uri(*) PREFIX pre(*) PRINT mypath END-PARSE
Output of the program:
nat:employee nat:employee/@nat:personnel-id nat:employee/@xmlns:nat nat:employee/nat:full-Name nat:employee/nat:full-Name/nat:first-name nat:employee/nat:full-Name/nat:first-name/$ nat:employee/nat:full-Name/nat:first-name// nat:employee/nat:full-Name/nat:name nat:employee/nat:full-Name/nat:name/$ nat:employee/nat:full-Name/nat:name// nat:employee/nat:full-Name// nat:employee//