XData Blocks

Describes the structure of an XData block.

Introduction

An XData block is a named unit of data that you include in a class definition, typically for use by a method in the class. Most frequently, it is a well-formed XML document, but it could consist of other forms of data, such as JSON.

Details

An XData block has the following structure:

/// description XData name [ keyword_list ]  { data }

Where:

description (optional) is intended for display in the Class Reference. The description is blank by default. See “Creating Class Documentation” in Using Caché Objects.
name (required) is the name of the XData block. This must be a valid class member name, and must not conflict with any other class member names.
data (optional) contains the payload of the XData block. If XML, it must be a well-formed document (with a single root element), without the XML declaration at its start.
keyword_list (optional) is a comma-separated list of keywords that further define the XData block.
See the section “XData Keywords.”
If this list is omitted, also omit the square brackets.

Example

XData Contents [ XMLNamespace="http://www.intersystems.com/zen" ]
{
  <page xmlns="http://www.intersystems.com/zen" title="HelpDesk">
    <html id="title">My Title</html>
    <hgroup>
      <pane paneName="menuPane"/>
      <spacer width="20"/>
      <vgroup width="100%" valign="top">
        <pane paneName="tablePane"/>
        <spacer height="20"/>
        <pane paneName="detailPane"/>
      </vgroup>
    </hgroup>
  </page>
}

XData Blocks

Introduction

Details

Example

See Also