How can I get to the data inside a returned JsonResult in my UnitTest?

Question

I have a controller method that returns a JsonResult like this:

    public ActionResult GetZipByState(string stateId)
    {
        var result =
            _mediator.Send<List<ZipCodeModel>>(new ZipCodeByStateQuery()
            {
                StateId = stateId
            });

        return Json(new { ZipCodes = result }, JsonRequestBehavior.AllowGet);
    }

Then I have this Unit Test:

    [Fact]
    public void GetZipByState_CanGetZipCodesByStateId()
    {
        // Arrange
        _mockMediator.Setup(m => m.Send<List<ZipCodeModel>>(It.Is<ZipCodeByStateQuery>(plist => plist.StateId == "VA")))
           .Returns(new List<ZipCodeModel>()
           {
                new ZipCodeModel(){ ZipCodeId = "7690", ZipCode = "24210" },
                new ZipCodeModel(){ ZipCodeId = "7691", ZipCode = "24211" },
                new ZipCodeModel(){ ZipCodeId = "7692", ZipCode = "24212" }
           });

        // Act
        //var actual = _controller.GetZipByState("VA");
        JsonResult actual = _controller.GetZipByState("VA") as JsonResult;
        List<ZipCodeModel> result = actual.Data as List<ZipCodeModel>;

        // Assert
        Assert.Equal("24211", (dynamic)actual.Data);
    }

I can see the data I need to get to in my Json under:

actual.Data.ZipCodes[1] in this screen shot:

But when I try to put the actual.Data into the result var and then do the assert, it is telling me that result is null.

How are you supposed to do this?

You cannot simply cast jsonresult data to any type. You need to use json serializer to deserialize it to the target type object — Chetan, Nov 02 '17 at 00:19
Looks like it is the same as here. [https://stackoverflow.com/questions/25875658/converting-jsonresult-into-a-different-object-in-c-sharp](https://stackoverflow.com/questions/25875658/converting-jsonresult-into-a-different-object-in-c-sharp) — Cedar, Nov 02 '17 at 03:02
Take a look at this answer I gave to a similar question https://stackoverflow.com/a/38446754/5233410 — Nkosi, Nov 02 '17 at 09:57

score 1 · Accepted Answer · answered Nov 02 '17 at 03:23

Your problem is that you are casting to wrong type.

This line here: List<ZipCodeModel> result = actual.Data as List<ZipCodeModel>; should be changed to

var result = actual.Data.GetType()
.GetProperties(BindingFlags.Instance | BindingFlags.Public)
.FirstOrDefault(x => x.Name == "ZipCodes")
.GetValue(actual.Data) as List<ZipCodeModel>;

How can I get to the data inside a returned JsonResult in my UnitTest?

1 Answers1