可以'；t将jQuery post数据发送到MVC控制器

我尝试过在谷歌上找到的解决方案，但没有任何帮助。我的ajax功能：

$.ajax({
        type: "post",
        url: apiEndpoint + "/CreateExercise", 
        data: JSON.stringify(data),
        datatype: "json",
        contentType: "application/json",
        success: function (result) {
            console.log(result);
        },
        error: function (xhr, status, p3, p4) {
            var err = "Error " + " " + status + " " + p3 + " " + p4;
            if (xhr.responseText && xhr.responseText[0] === "{") {
                err = JSON.parse(xhr.responseText).Message;
            }
            console.log(err);
        }
    });

MVC控制器：

public ActionResult CreateExercise(string sessionId, Exercise ExerciseCreateInfo)

我想要发送的数据：

data.sessionId =  sessionId;
    data.ExerciseCreateInfo = {};
    data.ExerciseCreateInfo.IsVisible = true;
    data.ExerciseCreateInfo.SimilarityNorm = $("#numSimilarityScore").val();
    data.ExerciseCreateInfo.TypeId = $("#selectTaskType option:selected").val();
    data.ExerciseCreateInfo.Name = $("#textTaskName").val();
    data.ExerciseCreateInfo.Difficulty = $("#numDifficulty").val();
    data.ExerciseCreateInfo.MarkPoints = $("#numPoints").val();
    data.ExerciseCreateInfo.Question = tinyMCE.get("editorTask").getContent();
    data.ExerciseCreateInfo.Hint = tinyMCE.get("editorHint").getContent();
    data.ExerciseCreateInfo.Explanation = tinyMCE.get("editorExpenation").getContent();
    data.ExerciseCreateInfo.Fields = {};