Getting around pain points of using a question mark in Html.ActionLink in Razor

There are two problems one might have with this:

@Html.ActionLink(@item.Name, "Details?Id=" + @item.Id)

They are:

1. This error appears:
   
   A potentially dangerous Request.Path value was detected from the client (?).
   

    
   ...for which the cure is to put the following in the system.web section of the Web.config:

   <httpRuntime requestValidationMode="2.0" requestPathInvalidCharacters="" />

   <pages validateRequest="false" />

2. The HTML comes out as:
   
   <a href="/Whatever/Details%3fId%3d3ab1172a-6d38-406a-a1f4-36726743226e">Foo</a>
   

    
   ...and you don't care for the encoding. The fix:

   @MvcHtmlString.Create(@Html.ActionLink(@item.Name, "Details?Id=" + @item.Id).ToString().Replace("%3f", "?").Replace("%3d", "="))

Yay!

While I was struggling to figure this out, I learned the following:

1. The third parameter here is the Controller:
   

   @Html.ActionLink("Help Page", "Help", "Home")

2. This is an example of creating a variable outside of a foreach loop
   

   @{
   
      var foo = "bar";
   
   }
   
   @foreach(var baz in qux)
   
   {
   
      @foo<br />
   
   }

3. These are some good links:
   
   1. http://haacked.com/archive/2011/01/06/razor-syntax-quick-reference.aspx
   2. http://stackoverflow.com/questions/4158975/set-value-of-var-in-foreach-razor-view-engine