External hyperlinks

External hyperlinks make it possible to link from the comment or from the function block documentation to an external website or to open an email program.

Hyperlink reference

Description

The hyperlink reference consists of a reference name followed by an underscore:

reference-name_

Phrase references must be specified in back quotes:

`reference name`_

(See also: Reference names)

Start and end characters

  • No start character, end character = "_"
  • Start character = "`", end character = "`_" (phrase references)

(See also: Inline markup)

Hyperlink target

Description

The hyperlink target consists of an explicit markup start (".. "), an underscore, the reference name, a colon, spaces and a link block:

.. _reference-name: link-block

A phrase reference in the hyperlink target can optionally be included in back quotes:

.. _`reference name`: link-block
.. _reference name: link-block

(See also: Explicit markup blocks, Reference names)

Principle

+-----+-----------------+
|".. "|"_"name":" link  |
+-----+block            |
      |                 |
      +-----------------+

Properties

  • External hyperlink targets have an absolute URI or an email address in their link block.
  • The URI of an external hyperlink can either start in the same line as the explicit markup or in an indented text block immediately afterwards, without blank lines between them.
  • If there are several lines in the link block, they are concatenated. Line breaks in the link block are removed. The following external reference targets are therefore equivalent:
.. _one-liner: https://infosys.beckhoff.de/

.. _starts-on-this-line: http://
   infosys.beckhoff.de/

.. _entirely-below:
   https://infosys.
   beckhoff.de/

If the URI of an external hyperlink target contains an underscore as the last character, this must be escaped so as not to be confused with an indirect reference target (see Escaping mechanism).

Sample

By clicking on the hyperlink reference, the website is called up directly in the Library Manager or a corresponding email program is opened.
(In sample project: B_DocuElements\Hyperlinks\FB_Libdoc_ExternalHyperlinks)

(*
See the Beckhoff_ home page for more information.

Please contact the `Beckhoff Support`_ for technical assistance.

.. _Beckhoff: http://www.beckhoff.de
.. _Beckhoff Support: support@beckhoff.com

For more information see the `PLC Lib Tc2_System`_ and `PLC Lib Tc2_Standard`_.

.. _PLC Lib Tc2_System: https://download.beckhoff.com/download/document/automation/twincat3/TwinCAT_3_PLC_Lib_Tc2_System_EN.pdf
.. _PLC Lib Tc2_Standard: https://download.beckhoff.com/download/document/automation/twincat3/TwinCAT_3_PLC_Lib__Tc2_Standard_EN.pdf
*)

External hyperlinks 1:

External hyperlinks 2:

External hyperlinks 3:

External hyperlinks 4:

It is also possible to include URIs directly in references.

(*
External hyperlinks, like `Beckhoff <http://www.beckhoff.de/>`_.
*)

External hyperlinks 5:

See also: Embedded URIs and aliases

Further Information