title: Change default ASP MVC Request Header to add your own values
body: <p>Im trying to change all my ASP MVC HTTP response headers to have another value by default for implementing Pingback auto-discovery in my blog application.</p>
  
  <p>The default header (on Cassini) is :</p>
  
  <pre><code>Cache-Control   private
  Connection  Close
  Content-Length  20901
  Content-Type    text/html; charset=utf-8
  Date    Fri, 20 Apr 2012 22:46:11 GMT
  Server  ASP.NET Development Server/10.0.0.0
  X-AspNet-Version    4.0.30319
  X-AspNetMvc-Version 3.0
  </code></pre>
  
  <p>and i want an extra value added : </p>
  
  <pre><code>X-Pingback: http://localhost:4912/pingback/xmlrpcserver
  </code></pre>
  
  <p>I have googled a bit and found a neet solution : 
  -- to derive from <strong>ActionFilterAttribute</strong> and override the <strong>OnResultExecuted</strong> method:</p>
  
  <pre><code>public class HttpHeaderAttribute : ActionFilterAttribute
      {
  
          public string Name { get; set; }
          public string Value { get; set; }
  
          public HttpHeaderAttribute(string name, string value)
          {
              Name = name;
              Value = value;
          }
  
          public override void OnResultExecuted(ResultExecutedContext filterContext)
          {
              filterContext.HttpContext.Request.Headers.Add(Name, Value);
              base.OnResultExecuted(filterContext);
          }
  
      }
  </code></pre>
  
  <p>And then simply i put the attribute on my Controllers methods:</p>
  
  <pre><code>[HttpHeader("X-Pingback","http://localhost:4912/pingback/xmlrpcserver")]
          public ActionResult Index()
          {
              var allArticles = _repository.GetPublishedArticles(SortOrder.desc);
              return View(allArticles);
          }
  </code></pre>
  
  <p>When i runt the app i get the following error :
  <img src="https://i.stack.imgur.com/mhIor.jpg" alt="enter image description here"></p>
  
  <p>Any ideas?</p>