Creating an Edit API Controller ASP.NET MVC

Question

I have created a get get by id and a delete api controller that are working just fine. What I am having problems with is creating an edit all the data by id. My examples of my api controllers look as:

[Authorize]
[Route("api/complaints")]
//get all
[HttpGet("")]
    public JsonResult Get()
    {
        var complaints = _repository.GetAll();
        var results = Mapper.Map<IEnumerable<CoViewModel>>(comps);
        return Json(results);
    }
//get by id
[HttpGet("{id}", Name = "GetByIdComp")]
    public IActionResult GetById(int id)
    {
        var complaints = _repository.GetById(id);
        if (complaints == null)
        {
            return HttpNotFound();
        }

        return new ObjectResult(comps);
    }
//delete by id
[HttpDelete("{id}")]
    public void Delete(int id)
    {
        _repository.Remove(id);
        _repository.SaveAll();
    }

//update/edit api not working
[HttpPut("{id}")]
    public JsonResult Post([FromBody] CoViewModel vm, int id)

    {
        try
        {
            if (ModelState.IsValid)
            {
                var obj = Mapper.Map<COMP>(vm);
                //Mapping from VM to Entities
                _logger.LogInformation("made a change");
                COMPLAINT updated = _repository.UpdateComp(obj, id);
                Response.StatusCode = (int)HttpStatusCode.Accepted;
                return Json(Mapper.Map<CoViewModel>(updated)); //Mapping from Ents to VM for the client
            }
        }
        catch (Exception ex)

        {
            _logger.LogError("N'error", ex);
            Response.StatusCode = (int)HttpStatusCode.BadRequest;
            return Json(new { Message = ex.Message });
        }

        Response.StatusCode = (int)HttpStatusCode.BadRequest;
        return Json(new { Message = "Failed", ModelState = ModelState });
    }

My repository for my api controller is this:

        public COMP UpdateComp(COMP newObj, int idOriginal)

    {

        var original = _context.Comps.FirstOrDefault(m => m.ID == idOriginal);
//Other related tables to update
        //original.CHECKLISTs = newObj.CHECKLISTs;
        //original.Division = newObj.Division;
        _context.SaveChanges();
        return original;
    }

When I try to use postman to change by id and put in the http and seend in a put or post, I get the error:

{message": "Failed",
"modelState": {
"": {
  "rawValue": null,
  "attemptedValue": null,
  "errors": [
    {
      "exception": {
        "ClassName": "Newtonsoft.Json.JsonReaderException",
        "Message": "Unexpected character encountered while parsing number: W. Path '', line 1, position 6.",
        "Data": null,
        "InnerException": null,
        "HelpURL": null,
        "StackTraceString": "   at Newtonsoft.Json.JsonTextReader.ReadNumberIntoBuffer()\r\n   at Newtonsoft.Json.JsonTextReader.ParseNumber()\r\n   at Newtonsoft.Json.JsonTextReader.ParseValue()\r\n   at Newtonsoft.Json.JsonTextReader.ReadInternal()\r\n   at Newtonsoft.Json.JsonTextReader.Read()\r\n   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.ReadForType(JsonReader reader, JsonContract contract, Boolean hasConverter)\r\n   at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize(JsonReader reader, Type objectType, Boolean checkAdditionalContent)",
        "RemoteStackTraceString": null,
        "RemoteStackIndex": 0,
        "ExceptionMethod": "8\nReadNumberIntoBuffer\nNewtonsoft.Json, Version=6.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed\nNewtonsoft.Json.JsonTextReader\nVoid ReadNumberIntoBuffer()",
        "HResult": -2146233088,
        "Source": "Newtonsoft.Json",
        "WatsonBuckets": null
      },
      "errorMessage": ""
    }
  ],
  "validationState": 1
},
"id": {
  "rawValue": "909",
  "attemptedValue": "909",
  "errors": [],
  "validationState": 2
}
}
}

Answer 1

Is there any chance that you have any HTTP Headers that are being included in your request by default (or any other data besides your object)?

Based on your error message, it looks like your application is attempting to serialize your request but sees an expected character and subsequently blows up. I'd recommend ensuring that you are actually passing your proper data (and just your data) and ensuring that it in the format you expect.

You'll want to ensure that you are send the data through Postman as raw.