我正在尝试在 SQLite ASP.Net Core 中使用 EntityFramework Core 。
当我处于调试模式时（使用Visual Studio），一切正常。
当我发布它，并且我正在尝试接收数据时，它正在工作。
数据读取控制器是这样的 -
[HttpGet]
public async Task<IActionResult> Get(int start=0,int end=0)
{
var bulletins = await _context.Bulletin
.Include(u => u.Descriptions)
.Include(u => u.Images)
.ToArrayAsync();
var response = bulletins.Select(u => new
{
Id = u.Id,
UserId = u.UserId,
Title = u.Title,
Descriptions = u.Descriptions.Select(p => p.Text),
Images = u.Images.Select(p => p.Name),
BaseUrl = "localhost/uploads/"
});
return Ok(response);
}
但是当我试图保存这样的数据时 -
[HttpPost]
public IActionResult Insert(BulletinViewModel data, ICollection<IFormFile> image)
{
List<Description> bulletinDescription = new List<Description>();
foreach (var description in data.text)
{
bulletinDescription.Add(new Description{ Text = description });
}
//string filename1 = _environment.WebRootPath;
List<Image> bulletinImages = new List<Image>();
string path = Directory.GetCurrentDirectory();
foreach (var file in image)
{
string fileName = Path.GetFileNameWithoutExtension(file.FileName);
string extention = Path.GetExtension(file.FileName);
var filename = ( data.user_id
+ "_"
+ Guid.NewGuid().ToString()
+ "_"
+ fileName
+extention).Trim('"');
bulletinImages.Add(new Image { Name = filename });
var serverFile = uploadDirectory + $@"/{filename}";
//file.Length;
using (FileStream fileStream = System.IO.File.Create(serverFile))
{
file.CopyTo(fileStream);
fileStream.Flush();
}
}
Bulletin bulletin = new Bulletin {
UserId = data.user_id,
Title = data.title,
Descriptions = bulletinDescription,
Images = bulletinImages
};
_context.Bulletin.Add(bulletin);
_context.SaveChanges();
return Ok(bulletin);
}
不在生产中（发布后），而在调试模式下工作（使用visual studio）。
我正在考虑此错误（此处给出总日志） -
Hosting environment: Production
Content root path: D:\Publish
Now listening on: http://localhost:5000
Application started. Press Ctrl+C to shut down.
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[1]
Request starting HTTP/1.1 GET http://localhost:5000/api/bulletin/get
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (4ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (3ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT COUNT(*) FROM "sqlite_master" WHERE "type" = 'table' AND "rootpage" IS NOT NULL;
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[1]
Executing action method BugTracker.api.BulletinController.Get (BugTracker) with arguments (0, 0) - ModelState is Valid
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (1ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT "u"."Id", "u"."Title", "u"."UserId"
FROM "Bulletin" AS "u"
ORDER BY "u"."Id"
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (1ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT "i"."Id", "i"."BulletinId", "i"."Name"
FROM "Image" AS "i"
WHERE EXISTS (
SELECT 1
FROM "Bulletin" AS "u"
WHERE "i"."BulletinId" = "u"."Id")
ORDER BY "i"."BulletinId"
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (1ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT "d"."Id", "d"."BulletinId", "d"."Text"
FROM "Description" AS "d"
WHERE EXISTS (
SELECT 1
FROM "Bulletin" AS "u"
WHERE "d"."BulletinId" = "u"."Id")
ORDER BY "d"."BulletinId"
info: Microsoft.AspNetCore.Mvc.Internal.ObjectResultExecutor[1]
Executing ObjectResult, writing value Microsoft.AspNetCore.Mvc.ControllerContext.
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[2]
Executed action BugTracker.api.BulletinController.Get (BugTracker) in 4224.5672ms
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[2]
Request finished in 5902.4455ms 200 application/json; charset=utf-8
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[1]
Request starting HTTP/1.1 POST http://localhost:5000/api/bulletin/insert multipart/form-data; boundary=----WebKitFormBoundaryGALOJJbtKdvvVFah 2532310
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
SELECT COUNT(*) FROM "sqlite_master" WHERE "type" = 'table' AND "rootpage" IS NOT NULL;
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[1]
Executing action method BugTracker.api.BulletinController.Insert (BugTracker) with arguments (BugTracker.Model.ViewModels.BulletinViewModel, System.Collections.Generic.List`1[Microsoft.AspNetCore.Http.IFormFile]) - ModelState is Valid
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
PRAGMA foreign_keys=ON;
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (4ms) [Parameters=[@p0='?', @p1='?'], CommandType='Text', CommandTimeout='30']
INSERT INTO "Bulletin" ("Title", "UserId")
VALUES (@p0, @p1);
SELECT "Id"
FROM "Bulletin"
WHERE changes() = 1 AND "Id" = last_insert_rowid();
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[@p2='?', @p3='?'], CommandType='Text', CommandTimeout='30']
INSERT INTO "Description" ("BulletinId", "Text")
VALUES (@p2, @p3);
SELECT "Id"
FROM "Description"
WHERE changes() = 1 AND "Id" = last_insert_rowid();
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[@p0='?', @p1='?'], CommandType='Text', CommandTimeout='30']
INSERT INTO "Description" ("BulletinId", "Text")
VALUES (@p0, @p1);
SELECT "Id"
FROM "Description"
WHERE changes() = 1 AND "Id" = last_insert_rowid();
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[@p0='?', @p1='?'], CommandType='Text', CommandTimeout='30']
INSERT INTO "Image" ("BulletinId", "Name")
VALUES (@p0, @p1);
SELECT "Id"
FROM "Image"
WHERE changes() = 1 AND "Id" = last_insert_rowid();
info: Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommandBuilderFactory[1]
Executed DbCommand (0ms) [Parameters=[@p0='?', @p1='?'], CommandType='Text', CommandTimeout='30']
INSERT INTO "Image" ("BulletinId", "Name")
VALUES (@p0, @p1);
SELECT "Id"
FROM "Image"
WHERE changes() = 1 AND "Id" = last_insert_rowid();
info: Microsoft.AspNetCore.Mvc.Internal.ObjectResultExecutor[1]
Executing ObjectResult, writing value Microsoft.AspNetCore.Mvc.ControllerContext.
fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[0]
An unhandled exception has occurred: Self referencing loop detected for property 'bulletin' with type 'BugTracker.DbModels.Mcp.Bulletin'. Path 'descriptions[0]'.
Newtonsoft.Json.JsonSerializationException: Self referencing loop detected for property 'bulletin' with type 'BugTracker.DbModels.Mcp.Bulletin'. Path 'descriptions[0]'.
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CheckForCircularReference(JsonWriter writer, Object value, JsonProperty property, JsonContract contract, JsonContainerContract containerContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CalculatePropertyValues(JsonWriter writer, Object value, JsonContainerContract contract, JsonProperty member, JsonProperty property, JsonContract& memberContract, Object& memberValue)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeList(JsonWriter writer, IEnumerable values, JsonArrayContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize(JsonWriter jsonWriter, Object value, Type objectType)
at Newtonsoft.Json.JsonSerializer.SerializeInternal(JsonWriter jsonWriter, Object value, Type objectType)
at Microsoft.AspNetCore.Mvc.Formatters.JsonOutputFormatter.WriteObject(TextWriter writer, Object value)
at Microsoft.AspNetCore.Mvc.Formatters.JsonOutputFormatter.<WriteResponseBodyAsync>d__9.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeResultAsync>d__32.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeResultFilterAsync>d__31.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeAllResultFiltersAsync>d__29.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeResourceFilterAsync>d__23.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeAsync>d__18.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Builder.RouterMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.ApplicationInsights.AspNetCore.ExceptionTrackingMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.<Invoke>d__6.MoveNext()
warn: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[0]
The response has already started, the error handler will not be executed.
fail: Microsoft.AspNetCore.Server.Kestrel[13]
Connection id "0HKUCLKEV7G2Q": An unhandled exception was thrown by the application.
Newtonsoft.Json.JsonSerializationException: Self referencing loop detected for property 'bulletin' with type 'BugTracker.DbModels.Mcp.Bulletin'. Path 'descriptions[0]'.
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CheckForCircularReference(JsonWriter writer, Object value, JsonProperty property, JsonContract contract, JsonContainerContract containerContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CalculatePropertyValues(JsonWriter writer, Object value, JsonContainerContract contract, JsonProperty member, JsonProperty property, JsonContract& memberContract, Object& memberValue)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeList(JsonWriter writer, IEnumerable values, JsonArrayContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize(JsonWriter jsonWriter, Object value, Type objectType)
at Newtonsoft.Json.JsonSerializer.SerializeInternal(JsonWriter jsonWriter, Object value, Type objectType)
at Microsoft.AspNetCore.Mvc.Formatters.JsonOutputFormatter.WriteObject(TextWriter writer, Object value)
at Microsoft.AspNetCore.Mvc.Formatters.JsonOutputFormatter.<WriteResponseBodyAsync>d__9.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeResultAsync>d__32.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeResultFilterAsync>d__31.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeAllResultFiltersAsync>d__29.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeResourceFilterAsync>d__23.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.<InvokeAsync>d__18.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Builder.RouterMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.ApplicationInsights.AspNetCore.ExceptionTrackingMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.<Invoke>d__6.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.<Invoke>d__6.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.ApplicationInsights.AspNetCore.RequestTrackingMiddleware.<Invoke>d__4.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Builder.Extensions.MapMiddleware.<Invoke>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Hosting.Internal.RequestServicesContainerMiddleware.<Invoke>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Frame`1.<RequestProcessingAsync>d__2.MoveNext()
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[2]
Request finished in 12477.1332ms 200 application/json; charset=utf-8
有人可以帮忙吗？
提前感谢您的帮助。
答案 0 :(得分：0)
相关错误的部分是
发生了未处理的异常：检测到自引用循环 对于'BugTracker.DbModels.Mcp.Bulletin'类型的属性'bulletin'。 路径'描述[0]'。 Newtonsoft.Json.JsonSerializationException： 检测到具有类型的属性“公告”的自引用循环 'BugTracker.DbModels.Mcp.Bulletin'。路径'描述[0]'。 在Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CheckForCircularReference（JsonWriter） writer，Object value，JsonProperty属性，JsonContract契约， JsonContainerContract containerContract，JsonProperty
因此，在模型的某处，您有一个引用循环，其中一个属性引用另一个模型类，该模型类具有对包含原始属性的类的引用。
我建议只保存更新的项目而不尝试保存整个树。如果多个引用也被更改，那么您需要计算一个过程，其中参考循环不会保存在一个批处理中，而是作为第二个保存操作添加。
答案 1 :(得分：0)
感谢Adem Caglin表示感谢。
我做到了 -
services.AddMvc().AddJsonOptions(options => {
options.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
});
一切都很好:)。