When using ASP.NET MVC, what is the best way to update multiple page sections with one HTML.Action() method?

I have a pretty big ASP.NET MVC site with 100 controllers and thousands of actions. Previously the header image that was defined on the Site.Master page was hardcoded and I want to make it dynamic.

To do so, I added this line to my Site.Master file:

<%= Html.Action("GetHeaderTitle", "Home")%>

which just returns some HTML for the header title such as:

<span style='font-size:15px;'>My Header Title</span>

The issue is that <title> also had this same hard coded value. I could obviously create another HTML.Action to have it show the dynamic valid in the title, but now I am going back to the server twice for essentially the same information (not the exact same HTML as I don't want the span information, but the same logic on the server to get the data).

Is there a way to have an Html.Action return multiple snippets of HTML that I can updates in different places on my master page?

I think you're looking at it wrong - if retrieving of the title is a long operation then just cache the results and write different actions anyway.

// Controller
public string GetTitle()
{
    var title = (string)ControllerContext.HttpContext.Items["CachedTitle"];
    if (string.IsNullOrEmpty(title))
    {
        title = "some lengthy retrieval";
        ControllerContext.HttpContext.Items["CachedTitle"] = title;
    }
    return title;
}

public ActionResult GetTitleForTitle()
{
    return Content(GetTitle());
}

public ActionResult GetHeaderTitle()
{
    return Content("<span>"+ GetTitle() + "<span>");
}

Alternatively, you can cache it directly on the view, which is kind of evil (the simpler view the better):

 <%
   ViewBag.CachedTitle = Html.Action("GetHeaderTitle", "Home");
 %>
 ...
 <%= ViewBag.CachedTitle %>
 ...
 <%= ViewBag.CachedTitle %>