【发布时间】：2017-07-03 12:15:27
【问题描述】：
对于 api 和 json 序列化，我有点陌生。 我遇到了一个奇怪的输出。似乎我的 json 输出被截断或格式错误？
（我正在使用带有 .net core 2.0 和 entity framework core 2.0 preview2 的 web api）
postman出现如下错误：
Expected ',' instead of ''
但在检查原始数据时，我发现并非所有内容都在发送：
{
"id": 2,
"username": "c8bee98",
"firstname": "Firstname73",
"lastname": "Lastname73",
"creationDate": "2017-07-02T23:47:16.204588",
"activityDate": "2017-07-03T14:02:58.6982234+02:00",
"profilePictureURL": "ProfilePictureURL73",
"gender": 2,
"location": "POINT(25.1400680863951
-25.0786780636193)",
"appsetting": null,
"email": "Email73",
"isHidden": false,
"isBanned": false,
"feedback": [{
"id": 19,
"rating": 1,
"feedbackType": 0,
"message": "Message1",
"creationDate": "2017-07-02T23:47:18.2287331",
"userId": 2
我的控制器如下所示：
UserManager userManager = new UserManager();
[HttpGet]
public async Task<User> GetById(int id)
{
try
{
return await userManager.GetByIdAsync(id);
}
catch (Exception ex)
{
throw ex;
}
}
我的模型如下所示：
public class User
{
[DisplayName("Id")]
public int Id { get; set; }
private string username = Guid.NewGuid().ToString("N");
[Required(ErrorMessage = "Username is required")]
[DisplayName("Username")]
[StringLength(32)]
public string Username
{
get {
string shortusername = username;
return shortusername.Remove(0,25);
}
}
public string ResetUsername()
{
username = Guid.NewGuid().ToString("N");
return username;
}
[Required(ErrorMessage = "Firstname is required")]
[StringLength(50, ErrorMessage = "Firstname can only be 50 characters long")]
[DisplayName("Firstname")]
public string Firstname { get; set; }
[Required(ErrorMessage = "Lastname is required")]
[StringLength(50, ErrorMessage = "Lastname can only be 50 characters long")]
[DisplayName("Lastname")]
public string Lastname { get; set; }
[Required(ErrorMessage = "Creation date is required")]
[DisplayName("Creation Date")]
[DataType(DataType.Date)]
[Column(TypeName = "datetime2")]
[DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:yyyy-MM-dd}")]
public DateTime CreationDate { get; set; } = DateTime.Now;
[Required(ErrorMessage = "Last activity date could not be registered")]
[DisplayName("Last Activity Date")]
[DataType(DataType.Date)]
[Column(TypeName = "datetime2")]
[DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:yyyy-MM-dd}")]
private DateTime lastActivityDate;
public DateTime ActivityDate
{
get { return lastActivityDate; }
set { lastActivityDate = DateTime.Now; }
}
[DataType(DataType.ImageUrl)]
[StringLength(2000, ErrorMessage = "That link is to long!")]
[DisplayName("Profile Picture")]
public string ProfilePictureURL { get; set; }
[Required]
[DisplayName("Gender")]
public Gender Gender { get; set; } = Gender.Unknown;
private string location = "POINT (0 0)";
[Required]
[DataType("geography")]
[DisplayName("Location")]
public string Location
{
get { return location; }
}
public string SetLocation(double latitude, double longitude)
{
location = String.Format("POINT({0} {1})", longitude, latitude).Replace(',', '.');
return location;
}
public double GetLatitude()
{
return double.Parse(location.Split('(', ')')[0].Split(' ')[0]);
}
public double GetLongitude()
{
return double.Parse(location.Split('(', ')')[0].Split(' ')[1]);
}
[DisplayName("App Settings")]
public AppSetting Appsetting { get; set; }
[DisplayName("Email")]
[DataType(DataType.EmailAddress, ErrorMessage = "Invalid email" )]
[StringLength(320)]
public string Email { get; set; }
[Required]
[DisplayName("Hidden")]
public bool IsHidden { get; set; } = false;
[Required]
[DisplayName("Banned")]
public bool IsBanned { get; set; } = false;
//User can have multiple feedbacks
public IEnumerable<Feedback> Feedback { get; set; }
//User can have multiple reported users
public IEnumerable<Reported> ReportedUsers { get; set; }
//User can have multiple blocked users
public IEnumerable<Blocked> BlockedUsers { get; set; }
//User can have multiple connections
public IEnumerable<Connection> Connections { get; set; }
//User can have multiple categories
public IEnumerable<UserCategory> UserCategory { get; set; }
//User can have multiple roles
public IEnumerable<UserRole> UserRole { get; set; }
//User can have multiple messages
public IEnumerable<Message> Messages { get; set; }
//User can watch multiple advertisements
public IEnumerable<Advertisement> Advertisement { get; set; }
//User can watch multiple advertisements
public IEnumerable<UserAdvertisement> WatchedAdvertisement { get; set; }
//User can have multiple providers
public IEnumerable<UserProvider> UserProvider { get; set; }
}
有什么建议吗？
编辑：
我的反馈集合有 2 个项目（2 个反馈）。
仅显示 1 及其所有属性。
反馈模型：
public class Feedback
{
[DisplayName("Id")]
public int Id { get; set; }
[Required(ErrorMessage = "A rating is required")]
[DisplayName("Rating")]
public int Rating { get; set; }
[Required(ErrorMessage = "A feedbacksection is required")]
[DisplayName("Section")]
public FeedbackType FeedbackType { get; set; }
[DisplayName("Message")]
//[DataType("nvarchar(500)")]
[StringLength(500, ErrorMessage = "That message is to long!")]
public string Message { get; set; }
[Required(ErrorMessage = "Creation date is required")]
[DisplayName("Creation Date")]
[DataType(DataType.Date)]
[Column(TypeName = "datetime2")]
[DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0:yyyy-MM-dd}")]
public DateTime CreationDate { get; set; } = DateTime.Now;
[Required]
[DisplayName("User")]
public int UserId { get; set; }
public User User { get; set; }
}
【问题讨论】：
-
什么没有被发送？收藏品？
-
是的，但反馈是否有回馈给用户的参考？如果是，那么你有一个循环依赖。用户 -> 反馈 -> 用户 -> 反馈 -> 用户
-
这就是为什么我说：不要使用 EF 实体作为返回结果。创建不带自引用属性的 ViewModel/Dto，然后对其进行映射（即使用 AutoMapper，但仅适用于 EF 实体 -> Dto。从不来自 Dto -> EF 实体）
-
@Liam 我使用 Core 是因为我在 Amazon AWS 上制作多服务 API 网关（基本上我的 api 变成了 lambda 函数）
-
发布包括堆栈在内的整个异常可能会提供有关该问题的更多信息
标签： c# json asp.net-core