List always returns null value when sent from controller to index

Question

I've now tried like 20 different ways and Googled the issue but I'm still stuck. My list is always returning a null value. When I debug I can see the values are coming from the database, and everything seems fine.

But, when I use console.log to debug in the view, it is always null.

Here is my model:

public class GarageModel
{
    public int GarageId { get; set; }
    public int Values { get; set; }
}

C# Method:

public List <GarageModel> getRequestType(int garageId)
{
    List<GarageModel> newList = new List<GarageModel>();

    string sql = "SELECT GarageID, RequestProperty FROM GarageCrossRequestType 
                  WHERE GarageID = " + garageId;

    var cmd = new SqlCommand(sql, Connection);

    var dt = new DataTable();
    dt.Load(cmd.ExecuteReader());

    foreach (DataRow i in dt.Rows)
    {
        var model = new GarageModel();
        model.GarageId = Convert.ToInt32(i["GarageID"].ToString());
        model.Values = Convert.ToInt32(i["RequestProperty"].ToString());
        newList.Add(model);
    }

    return newList;
    // returns the values from database 
}

Javascript / jQuery:

 function editGarage(e) {
            e.preventDefault();
            var dataItem = this.dataItem($(e.currentTarget).closest("tr"));
            var garageId = dataItem.GarageId;
            countryId = dataItem.CountryId;
            name = dataItem.Name;
            customerNumberOfEditingGarage = dataItem.CustomerNumber;
            var Values = dataItem.Values;

            $.ajax({
                   type: 'POST',
                   url: '@Url.Action("getRequestType", "Garage")?garageId=' + garageId,
                   dataType: 'JSON',
                   data: {
                       Values: Values, garageId: garageId
                   },
            });
            console.log(garageId, Values);
            // always return correct garageId but null in Values
            // or whatever value is set to Values in the model

What am I missing?

Like I've said I've tried different methods, I've changed types between get/post, I've changed the method to bool, int et cetera, but I'm lost and honestly, not especially good at JavaScript/jQuery either, so I'll appreciate any help I can get.

To specify, the result I would like is simply to see the Values I get from the method/database to be shown when I use console.log to debug in the browser.

Likely unrelated to your current issue, but https://stackoverflow.com/questions/14376473/what-are-good-ways-to-prevent-sql-injection may be of interest. And by "may be" I mean "you need to read it immediately". — mjwills, Aug 18 '21 at 13:14
Your issue is that your `console.log(..)` is outside the ajax, so runs whether you run the ajax or not - your ajax request doesn't have a `success:` (or other callback) so your code as-is has no way to *receive* the response - so trying different get/post is irrelevant as you're ignoring the result when/if it *does* work. — freedomn-m, Aug 18 '21 at 13:26
Does this answer your question? [How to return the response from an asynchronous call](https://stackoverflow.com/questions/14220321/how-to-return-the-response-from-an-asynchronous-call) — freedomn-m, Aug 18 '21 at 13:35

Onur Gelmez · Accepted Answer · 2021-08-18T13:39:52.420

Your getRequestType method needs only one param and values not a parameter so send only garageId and you need to fill values when your ajax success

$.ajax({
    type: 'POST',
    url: '@Url.Action("getRequestType", "Garage")',
    dataType: 'JSON',
    data: {
        garageId: garageId
    },
    success: function(data){
        values = data;
        console.log(garageId, data);
    }
});

And controller method needs to return JsonResult instead of list

public JsonResult /*List<GarageModel>*/ getRequestType ...


return Json(newList, JsonRequestBehavior.AllowGet);

List always returns null value when sent from controller to index

1 Answers1