How to leave URL parameters unescaped in ASP.NET MVC?

Question

I\'ve noticed the returnurl URL parameter on the Stackoverflow login/logout links are not escaped but when I try to add path as a parameter to a route it gets escaped.

Answer 1

My solutionto a similar problem was to write my own extension. After digging around in the code I couldn't find a way to do it otherwise. Yours might look like this.

public static class HtmlHelperExtensions
{
    public static string LoginLinkWithReturnUrl( this HtmlHelper helper,
                                                 string linkText,
                                                 string action,
                                                 string controller,
                                                 string returnUrl,
                                                 object htmlAttributes )
    {
         TagBuilder builder = new TagBuilder("a");
         builder.Attributes.Add( "href",
                                  string.Format( "/{0}/{1}?returnurl={2}",
                                                 controller,
                                                 action,
                                                 returnUrl ) );
         var attrDict = new RouteValueDictionary( htmlAttributes );
         builder.MergeAttributes( attrDict );
         builder.InnerHtml = linkText;
         return builder.ToString();
    }
}

I think I had the same problem making and using a UrlHelper so I went with the string.Format mechanism instead. YMMV.