I have recently been working with Umbraco 5 (Jupiter), the newest version rebuilt from the ground up using ASP.NET MVC. One of the stranger issues that I ran into occurred after adding a Surface Controller, and a corresponding custom View to the pre-compiled site. The following error showed up after a build/save all:


The pre-application start initialization method Start on type System.Web.WebPages.Deployment.PreApplicationStartCode threw an exception with the following error message: Exception has been thrown by the target of an invocation.


Since I opened the site up as an ASP.NET MVC3 Web Site, adding the view added the following to the Web.config:

<add key="webpages:Enabled" value="true" />

Since it does this behind the scenes, I was confused about how the error started, and wasn’t able to catch it until doing a compare on a fresh Umbraco web.config, and the one that was in the project root. Hopefully this saves some of you some time

Errors · Web Site

I have had a number of people ask about the CheckBoxFor method, and why it renders a hidden input tag with a value of false alongside the checkbox input. Here’s an example:

@Html.CheckBoxFor(m => m.IsEnabled)

will render

<input id="IsEnabled" type="checkbox" value="true" name="IsEnabled">
<input type="hidden" value="false" name="IsEnabled">


The reason this is done is because a form will not post anything to the server for an unchecked checkbox. In ASP.NET MVC, most of the time you are going to want a “false” value to be posted to the model binder, so the hidden value of false is there so that a value is posted back whether the checkbox is checked or not. If the checkbox is not checked, the form value for “IsEnabled” will be “false”, and if it is checked, both values will be posted as “true,false”. The model binder understands this, and will automatically take the true value from the collection of values. I have read that Ruby on Rails and MonoRail also use a similar technique.

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