Resolve a URL from a Partial View (ASP.NET MVC)
Working on an ASP.NET MVC application and needed the ability to resolve a URL from a partial view. For example, I have an image I want to display, but I need to resolve the virtual path (say, ~/Content/Images/New.png) into a relative path that the browser can use, such as ../../Content/Images/New.png or /MyAppName/Content/Images/New.png. Astandard view derives from the System.Web.UI.Page class, meaning you have access to the ResolveUrl and ResolveClientUrl methods. Consequently, you can write markup/code like the following:' /The problem is that the above code does not work as expected in a partial view. What's a little confusing is that while the above code compiles and the page, when visited through a browser, renders, the call to Page.ResolveClientUrl returns precisely what you pass in, ~/Content/Images/New.png, in this instance. The browser doesn't know what to do with ~, it presumes it's part of the URL, so it sends the request to the server for the image with the ~ in the URL, which results in a broken image.I did a bit of searching online and found this handy tip from Stephen Walther - Using ResolveUrl in an HTML Helper. In a nutshell, Stephen shows how to create an extension method for the HtmlHelper class that uses the UrlHelper class to resolve a URL. Specifically, Stephen shows how to add an Image extension method to HtmlHelper. I incorporated Stephen's code into my codebase and also created a more generic extension method, which I named ResolveUrl.public static MvcHtmlString ResolveUrl(this HtmlHelper htmlHelper, string url)
{
var urlHelper = new UrlHelper(htmlHelper.ViewContext.RequestContext);
return MvcHtmlString.Create(urlHelper.Content(url));
}With this method in place you can resolve a URL in a partial view like so:' /Or you could use Stephen's Html.Image extension method (althoughmy more generic Html.ResolveUrl method could be used in non-image related scenarios where you needed to get a relative URL from a virtual one in a partial view). Thanks for the helpful tip, Stephen!Happy Programming!Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.
