Showing an Image on a masterpage based on the logged in user.

Question

So I have a masterpage that has an image whos source is a controller action returning a filestream.

The image will be different for each logged in user.

right now in my masterpage view i have this code wich relies on viewdata.

  <img id="dealerlogo" src='/Files/DealerImage/GetDealerLogo/<%=Html.Encode(ViewData["dealerid"]) %>' alt="" />

obviously the problem with this is that I will need to provide the viewdata containing the ID on everycontroller action returning a view that uses this master page, which is pretty much all of them. Is there a better way to do this? Like is there a way to get the username right in the view? Thanks!

Answer 1

You can use the Page.User.Identity.Name just like in the default logonusercontrol.aspx that is created for you when you create a new asp.net MVC site.

Welcome <b><%= Html.Encode(Page.User.Identity.Name ) %></b>

So for you, you would want something like this:

  <img id="dealerlogo" src='/Files/DealerImage/GetDealerLogo/<%=Html.Encode(Page.User.Identity.Name) %>' alt="" />

Answer 2

I assume your GetDealerLogo action method has a parameter of dealerid. It's better to write something like:

<img src="<%= Url.Action("GetDealerLogo", "DealerImage", new { dealerid = ViewData["dealerid"] }) %>" />

Nothing wrong with passing it in via ViewData. You might also consider a strongly-typed View or your own ViewPage base class which exposes a DealerId property.

To make it even cleaner, I really like T4MVC. It would allow you to write:

<img src="<%= Url.Action(MVC.DealerImage.GetDealerLogo(dealerid)) %>" />

And, even further :) you might create an Html helper, so you can write:

<%= Html.DealerLogo(dealerid) %>

Answer 3

You can easily encapsulate this logic in a [ChildActionOnly] Action that returns a partial view and then use new MVC 2 approach <% Html.RenderAction("GetUserPhoto", "User"); %> to have it everywhere in your view pages without passing ViewData in all actions.

Here's the solution:

[ChildActionOnly]
pubic ActionResult GetUserPhoto()
{
    ViewData["UserId"] = Page.User.Identity;
    return PartialView();
}

And in your view you use the same logic you used to show user image. Also you can directly send a FileResult to partial view to render image for you. In this approach you don't need to repeat ViewData["XXXX"] in all views and you need just to Render the new Partial View in your main Views.