Question

I have one asp.net mvc 3 application.

public ActionResult Students()
{ 
  return View();
}

When i request these actions thru browser, everything works fine. It returns appropriate views, but when such actions are called from another site(across domain) thru jQuery Ajax call, It give transport error.

as a result we need to return such views in JsonpResult type, but now the problem is how do browser load such views of type JsonpResult ? it doesn’t return html part of the view instead it asks browser to save view result of type Jsonp.

Any suggestion, how to solve this ?

thanks.

Answer 1

You could use the RenderPartialViewToString method shown in this answer to render the view to a string and then return the custom JsonpResult you have written:

public class StudentsController : Controller
{
    public ActionResult Index()
    {
        MyViewModel model = ...
        return new JsonpResult(new 
        {
            html = RenderViewToString("Index", model)
        });
    }

    public string RenderViewToString(string viewName, object model)
    {
        ViewData.Model = model;
        using (var sw = new 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();
        }
    }

    protected string RenderPartialViewToString(string viewName, object model)
    {
        if (string.IsNullOrEmpty(viewName))
        {
            viewName = ControllerContext.RouteData.GetRequiredString("action");
        }

        ViewData.Model = model;
        using (var sw = new StringWriter())
        {
            var viewResult = ViewEngines.Engines.FindPartialView(ControllerContext, viewName);
            var viewContext = new ViewContext(ControllerContext, viewResult.View, ViewData, TempData, sw);
            viewResult.View.Render(viewContext, sw);
            return sw.GetStringBuilder().ToString();
        }
    }
}

The JsonpResult class used here could be found in this post.

And now you could invoke this controller action using AJAX from another domain:

var url = 'http://example.com/students/index';
$.getJSON(url + '?callback=?', function (data) {
    alert(data.html);
});