Xml (XmlDoc function)

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Serialize XmlDoc as UTF-8 string (XmlDoc class)

The Xml function converts an XmlDoc to its textually represented XML document (this process is called serialization, because the text representation of a document is called the serial form).


%string = doc:Xml[( [options])]

Syntax terms

%string The string serialization of the XmlDoc, encoded in UTF-8.
doc XmlDoc expression, whose content is to be serialized.
options A blank delimited string that can contain one or more of the following options (but no repeats).

Note: These options are described in greater detail in "XmlDoc API serialization options".

  • AllowXmlDecl or NoXmlDecl
    Whether or not the serialization will contain the "XML Declaration" (<?xml version=...?>), if the value of the Version property is a non-null string, and if the XmlDoc is not empty. AllowXmlDecl is the default.
  • Indent n
    Inserts space characters and line-ends into the serialized string such that if the string is broken at the line-ends and displayed as a tree, the display of each lower level in the subtree is indented n spaces from the previous level's starting point. You must also specify CR, LF, or CRLF (see below).
  • CR (carriage-return), LF (linefeed), or CRLF (carriage-return followed by a linefeed)
    Inserts one of these line-end options to provide line breaks in the serialized output.
  • NoEmptyElt
    This deprecated option serializes all empty elements with a start tag followed by an end tag. The default is to serialize an empty element with an empty element tag (as in <middleName/>).

    NoEmptyElt is deprecated in order to deter users from using it to serialize HTML: The recommended approach for HTML is shown on the NoEmptyElement property page — some tags (<div>) require separate start and end tags, while other tags (<br>) do not allow separate start and end tags.

  • OmitNullElement
    An Element node that has no children and no Attributes will not be serialized, unless it is the top level Element in the subtree being serialized.
  • SortCanonical
    This deprecated option serializes namespace declarations and attributes in sorted order (from lowest to highest with Unicode code ordering). It is superseded by the Serial method ExclCanonical option.

Usage notes

  • Options may be specified in any case, for example, you can use either NoXmlDecl or noxmldecl, interchangeably.
  • The XmlDoc method object must be well-formed (that is, it must contain an Element node). For more information, see "Well-formed documents and validation".
  • Since the result of the Xml function has UTF-8 encoding, you cannot treat it as an EBCDIC string: for example, printing the string will not produce displayable characters. The "See Also" section below mentions some methods for obtaining an EBCDIC serialization of an XmlDoc.
  • You can use the Print method to display a document on the terminal, or to capture a displayable version of a document, but Print is used to insert line breaks and optional indentation, which may not be an accurate serialization of an XmlDoc.
  • As of Sirius Mods Version 7.6, Attribute values are always serialized within double-quotation-mark (") delimiters, and a double-quotation mark character in an attribute value is serialized as &quot;. Prior to Version 7.6, this convention was not strictly observed.


  1. The AddXml method of the HTtpRequest class has nearly the same options as the Xml function. The following fragment serializes an XmlDoc and sends it as a request to a web server.

    Note that if you use the Xml function and $Sock_Send directly, instead of using an HTTP Helper object, always use the BINARY option of $Sock_Send, because the result of the Xml function is UTF-8, rather than EBCDIC.

    %httpreq object httpRequest %httpresp object httpResponse %doc object xmlDoc %httpreq = new %doc = new %doc:loadXml('<inquire><stock>IBM</stock>' with - <dateRange/></inquire>', 'NoEmptyElt') %httpreq:URL = 'foo.com/bar' %httpreq:addXml(%doc) %httpresp = %httpreq:post('HTTP_CLIENT')

  2. The following fragment is a simple example for serializing an XmlDoc, which could then, for example, be sent on a transport such as MQ:

    %s longstring %s = %doc:xml

Request-cancellation errors

This list is not exhaustive: it does not include all the errors that are request cancelling.

  • doc object does not contain an Element.
  • An options setting is invalid.
  • Insufficient free space exists in CCATEMP.

See also

  • Use Print to display an XML document for debugging.
  • Use Serial with the EBCDIC option to obtain an EBCDIC serialization of an XML document.
  • Use WebSend to serialize an XmlDoc and send it as an HTTP response using Janus Web Server.
  • The string deserialization functions are LoadXml and WebReceive.