Conditions in DITA can be set at both the element and topic levels, offering flexibility in controlling the inclusion or exclusion of content based on specific criteria. This enables fine-grained control over conditional processing.

Element-Level Conditions:

Element-level conditions involve applying conditions to specific elements within a DITA topic.

These conditions allow for control of the inclusion or exclusion of individual elements, such as paragraphs, images, or other content.

Element-level conditions can be useful for scenarios which require the content creator to specify conditions for small sections of content within a topic.

Topic-Level Conditions:

Topic-level conditions are defined for the entire DITA topic.

These conditions control the inclusion or exclusion of the entire topic based on specific criteria.

Topic-level conditions are typically set in the topic’s metadata or within the topicref in a DITA map.

They are suitable for situations where entire topics may need to be included or excluded in the output.

Example:

A DITA documentation project for a software product includes a series of topics related to various features. There’s a need to apply conditions both at the element and topic levels based on audience segments (beginners and advanced users).

Element-Level Conditions:

  <p>Introduction to the software.</p>
  <p conkeyref="audience=beginner">This feature is for beginners.</p>
  <p conkeyref="audience=advanced">This advanced feature is for experienced users.</p>
  

In this example:

• The introductory paragraph is not conditioned and is included for all audiences.
• Element-level conditions are set for the feature descriptions based on the audience key, allowing specific content to be included for beginners and advanced users.

Topic-Level Conditions:

  <map>
    <topicmeta>
      <keywords>
        <keyword keyname="audience" keyscope="local">
          <keyword keyref="beginner" conaction="exclude" />
          <keyword keyref="advanced" conaction="exclude" />
        </keyword>
      </keywords>
    </topicmeta>
  </map>
  

In this example:

• Topic-level conditions are defined in the DITA map’s metadata using keywords and their conaction attributes.
• Topics with conaction=”exclude” will be excluded for the specified audience condition.

Topic-Level conditions can also be applied using the @conref attribute in the DITA map:

  <topicref href="beginner_topic.dita" conkeyref="audience=beginner" />
  <topicref href="advanced_topic.dita" conkeyref="audience=advanced" />
  

Here, the @conkeyref attribute on topicref elements is used to conditionally include or exclude entire topics based on the specified audience condition.