As title, I have a problem with this that I saw my array of the object is empty at the back end. For example, I've defined 2 classes at the back end...

    public class ScoreModel { 
        public string Subject { get; set; }
        public float Score { get; set; }
    }
    public class StudentTestModel
    {
        public string Name { get; set; }
        public ScoreModel[] Scores { get; set; }
    }

At the code shown upper, the classStudentTestModel has an array of ScoreModel that contains 2 simple data members. Then at the front end, I use jQuery library to call back end like this....

$("#btnCountScore").click(function () {
                var frm = new FormData();
                frm.append("Name", "Garfield");
                var r = [
                    { "Subject": "Chinese", "Score": 89 },
                    { "Subject": "English", "Score": 87 },
                    { "Subject": "Math", "Score": 76 },
                    { "Subject": "NaturalScience", "Score": 90 },
                    { "Subject": "SocialScience", "Score": 83 },
                ];
                var r_form = [];
                for (var i = 0; i < r.length; i += 1) {
                    var f = new FormData();
                    f.append("Subject", r[i].Subject);
                    f.append("Score", r[i].Score);
                    r_form.push(f);
                }
                frm.append("Scores", r_form);
                $.ajax({
                    url: "../Home/CountScore",
                    method: "post",
                    processData: false,
                    contentType: false,
                    data: frm,
                    success: function (ret) {
                        $("#lblShowAverage").text(ret);
                    }
                });
            });

When I debug, I can see the Name contains value but Scoures is an empty array at my back end, then I couldn't get what I want. Could someone guide me a way to correct this?