Question

I’ve created an extension method:

namespace MyComp.Web.MVC.Html
{
    public static class LinkExtensions
    {
        public static MvcHtmlString ActionImageLink(this HtmlHelper htmlHelper, string linkText, string imageSource, string actionName)
        {
            ...
        }
    }
}

I’ve referenced the assembly from my mvc app, and I’ve tried importing the namespace in my view:

<%@ Import Namespace="MyComp.Web.Mvc.Html" %>

and I’ve also added it to the web config file:

<pages>
    <controls>
        ...
    </controls>
    <namespaces>
        <add namespace="System.Web.Mvc"/>
        <add namespace="System.Web.Mvc.Ajax"/>
        <add namespace="System.Web.Mvc.Html"/>
        <add namespace="System.Web.Routing"/>
        <add namespace="System.Linq"/>
        <add namespace="System.Collections.Generic"/>
        <add namespace="MyComp.Web.Mvc.Html"/>
    </namespaces> 
</pages>

In My view if I try to access Html.ActionImageLink I get an error saying that System.Web.Mvc.HtmlHelper does not contain a definition for ActionImageLink accepting a first argument type of System.Web.Mvc.HtmlHelper. I don’t see any of the ActionLink extension methods for System.Web.Mvc.HtmlHelper, only for System.Web.Mvc.HtmlHelper, so how does it work for the .net framework, and not for me?

Answer 1

Notice the difference in the case of your namespace when declaring and when importing.

namespace MyComp.Web.MVC.Html
{
} 

<%@ Import Namespace="MyComp.Web.Mvc.Html" %>
<add namespace="MyComp.Web.Mvc.Html"/>

Namespaces are case-sensitive!