具有循环依赖性的EF模型的序列化

Question

我正在尝试序列化数据库模型。但是有一个错误。

这是我的模特：

public class Equipment
    {
        public int Id { get; set; }
        //Двигатель
        [Required]
        [Display(Name = "Двигатель")]
        public int Engine { get; set; }
        //Количество лошадиных сил
        [Required]
        [Display(Name = "Мощность")]
        public int Power { get; set; }
        //Год выпуска
        [Required]
        [Display(Name = "Год выпуска")]
        public int ReleaseYear { get; set; }
        //Тип привода
        [Required]
        [Display(Name = "Тип привода")]
        public string DriveType { get; set; }
        //КПП
        [Required]
        [Display(Name = "КПП")]
        public string Transmission { get; set; }
        //Кузов
        [Required]
        [Display(Name = "Кузов")]
        public string Body { get; set; }
        //Максимальная скорость
        [Required]
        [Display(Name = "Максимальная скорость")]
        public int MaxSpeed { get; set; }
        //Вес
        [Required]
        [Display(Name = "Вес")]
        public int Weight { get; set; }
        //Бак
        [Required]
        [Display(Name = "Бак")]
        public int MaxFuelVolume { get; set; }
        //Цвет автомобиля
        [Required]
        [Display(Name = "Цвет")]
        public string Color { get; set; }
        //Изорбражение автомобиля
        [Required]
        [Display(Name = "Изображение автомобиля")]
        public string Picture { get; set; }

        public int CarModelId { get; set; }
        public virtual CarModel CarModel { get; set; }
        public virtual ICollection<Car> Cars { get; set; }

        public Equipment()
        {
            Cars = new List<Car>();
        }
    }

这是我在控制器中用于序列化的代码：

return Json(JsonConvert.SerializeObject(car.Equipment));

这是错误产生的原因：

  

检测到类型为'System.Data.Entity.DynamicProxies.Equipment_4B2DAA6CED521984C9D15F5FEA2BB989D5DB7F80683721A0FC847726CB1C9ACB'的自引用循环。路径“ CarModel.Equipments”。

这是上课的人：

public class CarModel
    {
        public int Id { get; set; }

        [Display(Name = "Модель")]
        public string ModelName { get; set; }

        public int MarkId { get; set; }
        public virtual Mark Mark { get; set; }

        public virtual ICollection<Equipment> Equipments { get; set; }

        public CarModel()
        {
            Equipments = new List<Equipment>();
        }
    }

我尝试连接System.web.script.serialization并将脚本忽略属性设置为

public virtual CarModel CarModel { get; set; }
public virtual ICollection<Car> Cars { get; set; }

在装备课上及以后

public virtual ICollection<Equipment> Equipments { get; set; }

在CarModel类中，它仍然是相同的错误。

请告诉我如何避免此错误？以及如何序列化具有循环依赖性的模型？

ajax请求：

$('#autoList').on('change', function () {
        var ddlAuto = $('#autoList').val();
        if (!ddlAuto || ddlAuto === '')
            return false;

        $.ajax({
            type: "POST",
            url: "/Administration/GetCarInfo",
            data: {
                "carId": ddlAuto
            },
            success: function (data) {
                alert('ОК');
            }
        });
    });

但是在一种情况下，可以序列化，尽管它不是序列化为对象而是字符串。

序列化的结果，如果在控制器中写

return Json(JsonConvert.SerializeObject(car.Equipment, Formatting.Indented, new JsonSerializerSettings
            {
                PreserveReferencesHandling = PreserveReferencesHandling.Objects
            }));

"{
  "$id": "1",
  "CarModel": {
    "$id": "2",
    "Equipments": [
      {
        "$ref": "1"
      }
    ],
    "Mark": {
      "$id": "3",
      "CarModels": [
        {
          "$ref": "2"
        },
        {
          "$id": "4",
          "Equipments": [
            {
              "$id": "5",
              "CarModel": {
                "$ref": "4"
              },
              "Cars": [
                {
                  "$id": "6",
                  "Equipment": {
                    "$ref": "5"
                  },
                  "Orders": [
                    {
                      "$id": "7",
                      "Cars": {
                        "$ref": "6"
                      },
                      "Clients": {
                        "$id": "8",
                        "Orders": [
                          {
                            "$ref": "7"
                          },
                          {
                            "$id": "9",
                            "Cars": {
                              "$id": "10",
                              "Equipment": {
                                "$id": "11",
                                "CarModel": {
                                  "$ref": "4"
                                },
                                "Cars": [
                                  {
                                    "$ref": "10"
                                  }
                                ],
                                "Id": 30,
                                "Engine": 2500,
                                "Power": 170,
                                "ReleaseYear": 2011,
                                "DriveType": "Передний",
                                "Transmission": "Автомат",
                                "Body": "Седан",
                                "MaxSpeed": 220,
                                "Weight": 1800,
                                "MaxFuelVolume": 80,
                                "Color": "Чёрный"

我试图做其他事情

return Json(JsonConvert.SerializeObject(car.Equipment, Formatting.Indented, new JsonSerializerSettings
            {
                ReferenceLoopHandling = ReferenceLoopHandling.Ignore
            }));

然后发生错误：

  

“ System.OutOfMemoryException”

请告诉我我做错了什么？如何将模型序列化为对象以继续使用它？