<param>

The <param> (parameter) element specifies a set of values that might be required by an <object> at runtime. Any number of <param> elements might appear in the content of an <object> in any order, but must be placed at the start of the content of the enclosing object. This element is comparable to the XHMTL <param> element, and its attributes' semantics derive from their HTML definitions. For example, the @type attribute differs from the @type attribute on many other DITA elements.

Content models

See appendix for information about this element in OASIS document type shells.

Inheritance

- topic/param

Example

See <object>.

Attributes

The following attributes are available on this element: Universal attribute group and the attributes defined below.

@name (REQUIRED)

The name of the parameter.

@value

Specifies the value of a run-time parameter that is specified by the @name attribute.

@valuetype

Specifies the type of the @value attribute. Allowed values are:

data: A value of data means that the value will be evaluated and passed to the object's implementation as a string.
ref: A value of ref indicates that the value of the @value attribute is a URL that designates a resource where run-time values are stored. This allows support tools to identify URLs that are given as parameters.
object: A value of object indicates that the value of @valuetype is an identifier that refers to an object declaration in the document. The identifier must be the value of the ID attribute set for the declared object element.
-dita-use-conref-target: See Using the -dita-use-conref-target value for more information.

@type

This attribute specifies for a user agent the type of values that will be found at the URI designated by @value. Note that this differs from the @type attribute on many other DITA elements.

When @valuetype is set to "ref", this attribute directly specifies the content type of the resource designated by @value.
Otherwise, if @type is specified and @keyref is specified and resolvable, this attribute specifies the content type of the resource designated by @keyref.
Otherwise, if @type is not specified and @keyref is specified and is resolvable, the effective type value specified for the key that is named by the @keyref attribute is used as the value of the @type attribute.

@keyref

Key reference to the thing the parameter references. If @valuetype is specified but is not set to "ref", this attribute is ignored. When @valuetype is not specified and @keyref is specified, it implies a setting of valuetype="ref". When @keyref is specified and the effective value of @valuetype is "ref":

When the key specified by @keyref is resolvable and has an associated URI, that URI is used as the value of this element (overriding @value, if that is specified).
When the key specified by @keyref is resolvable and has no associated resource (only link text), the @keyref attribute is considered to be unresolvable for this element. If @value is specified, it is used as fallback.
When the key specified by @keyref is not resolvable, the value of the @value attribute is used as a fallback target for the <param> element.