How can I return my MVC4 partial view as json and is it a good thing to do?

Question

I am trying to clean up my code. I have a grid screen that gets refreshed with the following:

    public ActionResult Details(string pk)
    {
        IEnumerable<ContentDetail> model = null;
        try
        {
            model = _content.Details(pk);
            if (model.Count() > 0)
            {
                return PartialView(getView(pk) + "Details", model);
            }
        }
        catch (Exception e)
        {
            log(e);
        }
        return Content("No records found");
    }

All the rest of my code uses json and I would like to return something like this:

public JsonResult JsonDetails(string pk)

But what should I do about the PartialView? I can't find anything about how to do this. Also is there any advantage / disadvantage to doing this? I was thinking if the code fails then I would return something like the following which the new ASP MVC4 code uses:

return Json(new { errors = GetErrorsFromModelState() });

Can someone help me with this? I'm looking to find any suggestions in particular for MVC4.

score 6 · Answer 1 · edited May 23 '17 at 12:00

I've previously used the approach outlined in this answer, which was successful for me.

I can't think of any disadvantages of returning HTML within JSON, although the payload would likely be much larger than if you were returning data alone.

An alternative would be to return the model as JSON, and use a templating library, e.g. Handlebars.js, to generate the markup on the client. This is a common approach in single page applications.

Your idea around returning errors is good. GetErrorsFromModelState is only used where there are validation errors in the model state - in the example above, you're not performing any validation that would require you to use this method. So you'd probably want to output some friendly message within your catch-block, e.g.

try
{
    ...
}
catch (Exception e)
{
    log(e);
    return Json(new { errors = "An error occurred, please try again later" });
}

score 1 · Answer 2 · edited May 23 '17 at 12:14

1

I've used the code from this answer before and it worked out great for me, I haven't tried returning specific errors, but it is possible to access controller.ModelState to check.

edited May 23 '17 at 12:14

Community

1
1

answered Apr 25 '12 at 13:55

Madd0g

3,841
5
37
59

1

Thanks. I am wondering why ASP doesn't have this capability built in. Is this not something that many people would like to do? – Apr 25 '12 at 14:39

How can I return my MVC4 partial view as json and is it a good thing to do?

2 Answers2