Developing for MVC4 using Razor and JSON

Just playing around this weekend, I wanted some data listings in a page that did not post back in MVC. While not such a big deal in regular ASP, MVC does not have page event handlers in a code-behind file. There is instead a Controller class that you can call in Routing code.



First : the client side javascript handler, this is what is called when the Controller method completes.

  
  using (Ajax.BeginForm("SearchForms",
                       "DBForms",
                        new AjaxOptions() { 
                        OnSuccess="jsonFSearchComplete",                      
                        OnFailure="searchFail" }))
 
Then …
function jsonFSearchComplete(context) { 
   $("#DBFormsDiv").html(context.Data);
  }

Next, the Razor syntax for the page :

  @{using (Ajax.BeginForm("JsonSearchRequests",                       
   "Request",                       
   new AjaxOptions() { 
   OnComplete = "searchComplete", 
   OnFailure= "searchFail"
   }))

  // Not including the whole form I created here, just 
  //  labels and textboxes, etc..
}

Then the Controller code for getting the Partial view built and sent down (Got this from StackOverflow postings):

private string RenderRazorViewToString(string viewName)
{
using (var sw = new System.IO.StringWriter())
{
var viewResult =
ViewEngines.Engines.FindPartialView(ControllerContext, viewName);
var viewContext =
new ViewContext(ControllerContext, viewResult.View, ViewData, TempData, sw);
viewResult.View.Render(viewContext, sw);
viewResult.ViewEngine.ReleaseView(ControllerContext, viewResult.View);
return sw.GetStringBuilder().ToString();
}
}

For a form posting in a page, there must be a Controller method ( :

[AcceptVerbs(HttpVerbs.Post)]
public JsonResult JsonSearchRequests(string AccountNumber,
string Subfirm,
string RegistrationType)
{
Data d = new Data();

if (AccountNumber.Length > 0)
{
ViewData["Requests"] =
d.GetRequestsByAccount(AccountNumber);
}
else if (Subfirm.Length > 0)
{
ViewData["Requests"] =
d.GetDBRequests(Subfirm, RegistrationType)
.Skip(0).Take(100);
}
return Json(new { Data = RenderRazorViewToString("dbRequests") });
// Note the HttbVerb must be stated for Posting a form
}

For a link that a user can click in the page :

[AcceptVerbs(HttpVerbs.Get)]
public JsonResult JsonSelectDbRequest(string Id)
{
Data d = new Data();
ViewData["Generations"] = d.GetGenerations(Id);

return Json(new { Data = RenderRazorViewToString("dbGenerations") },
JsonRequestBehavior.AllowGet);
}

// Note the Http Verb for GET must be stated
}

Code for a Partial View of a list that does Ajax posting :

      @Ajax.ActionLink("SELECT",
                       "JsonSelectDbRequest",
                       "DocRequest",
                       new  { Id = req.REQUEST_ID },
                       new AjaxOptions() { OnComplete = "requestSelectComplete" });

EDIT: There is no need to include the old MVCAjax script files.