Lessons Learned Developing DNN Modules

Jumping into DNN development, here’s a couple of things I learned from developing my first modules.

Module Path

There are a couple of variables a module can derive its file system location (and thus relative URL paths) from:

ControlPath	/dnn/DesktopModules/MyModule/
ModulePath	/dnn/DesktopModules/MyModule/
Request.ApplicationPath	/dnn
Request.CurrentExecutionFilePath	/dnn/Default.aspx
ModuleConfiguration.ControlSrc	DesktopModules/MyModule/View.ascx

If you need to reference files in the file system, or URLs relative to the module’s installation path, this statement

var IncludePath = ModuleConfiguration.ControlSrc
  .Replace("/View.ascx", "/");

gives you the module’s base directory.

Packaging

You can freely edit the module’s .dnn file to edit the components of the installation.

For example, if the module has no Edit or Settings dialog, remove Edit.ascx* and/or Settings.ascx* from the .dnn file under

component/
  desktopModule/
    moduleDefinitions/
      moduleDefinition/
        moduleControls

as you remove or exclude them from the DNN project (.csproj file).

If you do not have an Edit form, disable the registration of the Edit form in the ModuleActions getter of View.ascx.cs.

For layout definition and CSS classes in your Edit.ascx, see the HTML\EditHtml.ascx that comes with DNN.

View/Edit Mode

If your View.ascx should behave differently depending on whether it is displaying in View mode or Edit mode, use the following markup to distinguish the two modes:

<%  if (!DotNetNuke.Common.Globals.IsEditMode())  {   %>
      <!-- markup for edit mode -->
<%  } else { %>
      <!-- markup for view mode -->
<%  } %>

Closing Forms

To close a dialog, simply redirect to the current page:

protected void cmdUpdate_Click(object sender, EventArgs e)
{
  try
  {
    UpdateSettings();
    Response.Redirect(Globals.NavigateURL(), true);
  }
  catch (Exception exc)
  {
    Exceptions.ProcessModuleLoadException(this, exc);
  }
}

JavaScript

DNN uses a combination of JavaScript libraries

• jQuery 1.6.4 (Resources/Shared/scripts/jquery) (org, com)
• json2
• AjaxControlToolkit
• DNN JS library (blog, blog)

Embedding DNN pages in iframes

A typical DNN page contains menu, header, content panes, and a footer. The default skin of DNN6 is called DarkKnight and provides a page skin called „Host: DarkKnight – popUpSkin“ with just a single content pane and no headers, footers, borders, etc., and is thus perfect for embedding DNN pages inside an <iframe> either in the same DNN installation or from outside.

Display Time Range

You can set the period to display a page using the Start Date and End Date settings in the Advanced Settings section of the Module Settings.

Start and End Dates are only settable on a day level, there is no built-in way to display modules based on time of day.

Automatic Refresh

Automatic Refresh is supported on page level, but not on module level.

A little warning: the refresh interval is also active in Edit mode, so if you set the interval too short, you may not be able to set it to a longer interval directly in the page. You need to navigate to Host/Page Management and reset the refresh interval.