Each topic is assigned a unique ID that can be referenced in topics using a link MAML element. Changes can be made to the topic properties such as the filename associated with the ID and its title text without having to visit each topic in which it is referenced. When creating new topics using the help file builder, templates are used and new ID and revision numbers are assigned automatically. The content layout editor tracks topics by ID rather than by filename. As such, you can rearrange and rename the files in the project without being concerned about updating references to them in the content layout files. As long as the ID remains the same, the same topic will be associated with the entry regardless of where it is moved or what it is named.

Note
The value of the ID assigned to a topic should not be changed. If it is, you will be required to manually locate and update the old ID in all topics that reference it.

Within the content layout editor, each topic contains several properties which are described below.

ID, Revision #, and Topic Filename

These read-only properties display the ID and revision number of the topic and the project file related to the ID. The three buttons to the right of the currently associated topic filename let you do the following:

• Associate Topic - The layout file tracks topics by their unique ID rather than by filename. This button allows you to associate a different topic file with a content layout file entry or add an association to an empty container node.

• Clear Topic Association - This button allows you to clear the topic file associated with a content layout file entry converting it into an empty container node. The node will not have a topic associated with it in the compiled help file nor will it display a topic when selected in the table of contents. It simply serves as a container for other topics and must have at least one child topic defined for it.

  Note
  The MS Help Viewer file format does not support empty container nodes. All entries must have an associated topic. If one is not specified, an empty topic will be generated at build time so that a valid help file is produced.

• Refresh Associations - If you move one or more files around or rename them in the Project Explorer, the currently open content layout file editor will not be aware of these changes. Use this button after making such changes so that the content layout editor refreshes the files associated with each topic. This allows you to open them for editing from the layout editor after moving or renaming them without closing and reopening the layout editor. This option refreshes the entire collection of topics, not just the one currently being viewed.

Title

This is used as the title for the topic. In addition, it will be used as the table of contents title unless a TOC Title value is specified. It will also be used as the link text unless a Link Text value is specified. If left blank, the topic filename is used as a default title.

TOC Title

This is used to specify an optional table of contents title for a topic. If not set, the Title value will be used. In some cases, the title may not be appropriate for the table of contents or is too long to be practical. In such cases you can specify shorter or more appropriate text for the table of contents via this property.

Link Text

This property can be used to specify an alternate value to use as the inner text for links. If not set, the Title value will be used. In some cases the title may not be appropriate or may be too long to be practical for links that refer to the topic. In such cases you can specify shorter or more appropriate text for the link via this property. This saves you from having to specify the shorter inner text on each link that uses the topic ID.

Show in the table of contents

This allows you to specify whether or not a topic will appear in the table of contents. The default is checked to show it. If unchecked, the topic will be included in the help file but will only be accessible via links from other topics. This is a convenient way of adding content to the help file but limiting the amount of information displayed in the table of contents. A hollow bullet point appears next to invisible topics in the content layout tree to note their status. Making a parent topic invisible will also remove its child topics from the table of contents.

Use as the default topic

This will mark the selected topic as the default topic for the help file. The default topic option acts as a toggle. Check it on a topic to set it as the default. If another topic was previously marked as the default topic, the option is removed from it. Unchecking it on the same topic turns it off and no topic will be selected as the default topic. In such cases, the root namespaces page will be the default topic for the help file. When set, a green circle icon with a checkmark appears next to the topic in the content layout tree to indicate its status.

Note
This option only has an effect on Help 1, Help 2, and Website output. MS Help Viewer does not support the specification of a default topic.

Use as MS Help Viewer root container

This option is useful if you are generating multiple help file formats from one project file including MS Help Viewer output. By default, all topics in the MS Help Viewer output are listed as root elements in their parent topic. If you would prefer them to be grouped under a common root container topic, add a topic to the content layout file and use this option to mark it as the root container. The root container must have its Show in the table of contents option unchecked so that it is not included in the table of contents. This prevents it from appearing in the other help file formats. It will be added automatically to the MS Help Viewer output when that format is built. If you want a root container to appear in all formats, simply add it as a normal topic in the content layout file and manually add all of the other topics to it as sub-topics. This option acts as a toggle. Check it on a topic to set it as the container. If another topic was previously marked as the container topic, the option is removed from it. For more information, see the Content Placement Options topic. When set, a file tree icon appears next to the topic in the content layout tree to indicate its status.

API Content

This is used to indicate how the API (reference) content for the help file should be inserted relative to the selected topic. The following options are available:

• None - This topic will not be used as the API content insertion point.

• Insert after this topic - The API content will be inserted immediately after this topic in the table of contents.

• Insert before this topic - The API content will be inserted immediately before this topic in the table of contents.

• Insert as child of this topic - The API content topics are added as sub-topics of the selected topic. If the selected topic already contains sub-topics, the API topics will appear after them.

This option acts as a toggle. Select a value other than None to make it the API content insertion point. If another topic was previously marked as the API content insertion point, the option is removed from it. An icon will appear next to the topic in the content layout tree to indicate its API content insertion point state. This option can be combined with the default topic option. If no topic is set as the API content insertion point, the API content will be added to the table of contents following the standard content placement rules.

Index Keywords

This grid allows you to add MSHelp:Keyword attributes to the help topic to define its index keywords. In the grid for this property, select the index and enter the terms for it. Keyword terms can contain substitution tags which will be converted to their appropriate value at build time. To delete a keyword, select it in the grid and hit the Delete key.

The most common index used in the "K" index (keywords). The terms consist of one word or a phrase. If you separate two terms with a comma, the first term becomes a group in the index. If that same grouping term appears in other topics, the term that follows the comma in each of them will appear as a child of the grouping term in the help file's index. If your intent is to add two terms to the same index but have them appear as two distinct entries, enter them on two separate rows in the grid.

Tip
If a topic is marked as the default using the designer, entries for the NamedUrlIndex terms DefaultPage and HomePage are added to it automatically at build time so there is no need to add them via this property.

Note
Keywords will only be added to MAML topics, not HTML files.

Help Attributes

This grid allows you to add custom MSHelp:Attr attributes to the topic. In the grid for this property, enter the property name and the value for it. Attribute values can contain substitution tags which will be converted to their appropriate value at build time. To delete an attribute, select it in the grid and hit the Delete key.

Tip
Project-level help attributes in the project HelpAttributes property will be added automatically to each topic at build time and do not need to be added here.

Note
Attributes will only be added to MAML topics, not HTML files.

Topic files can be named however you like and can reside in any folder within the project. As such, you can arrange them on disk to match the layout in the table of contents and give them meaningful names to aid in managing them outside of the project and the designer. When the help file is built, all topic files are copied to the help file's .\html folder and are named using their unique ID with a .htm extension. You can use that name to link to the topic from other HTML pages. For example:

Link to a topic from an HTML file in the .\html folder:
<a href="303c996a-2911-4c08-b492-6496c82b3edb.htm">Test Topic</a>

Link to a topic from the root folder:
<a href="html/303c996a-2911-4c08-b492-6496c82b3edb.htm">Test Topic</a>

Link to a topic from another folder:
<a href="../html/303c996a-2911-4c08-b492-6496c82b3edb.htm">Test Topic</a>

For XML comments, the preferred approach is to use the conceptualLink element to link to the topic ID. When used inline within another element, it creates an inline link. When used at the top-level like a summary or remarks element, it adds an entry to the See Also section of the API topic. For example:

/// <remarks>
/// See the <conceptualLink target="303c996a-2911-4c08-b492-6496c82b3edb" /> topic for more information.
/// </remarks>

/// <remarks>
/// More information can be found <conceptualLink
/// target="303c996a-2911-4c08-b492-6496c82b3edb">in this topic</conceptualLink>
/// </remarks>

/// <remarks>
/// This example adds an entry to the See Also section of the topic
/// </remarks>
/// <conceptualLink target="303c996a-2911-4c08-b492-6496c82b3edb" />

Other Resources