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可能な解決策をすべて実行しようとしましたが、正しい答えが得られませんでした。以下は私のコードです：Web APIエラー： 'ObjectContent`1'タイプのシリアル化に失敗しました
WebApiConfig.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.Http;
using System.Net.Http.Headers;
namespace WebAPI
{
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
// Web API configuration and services
// Web API routes
config.MapHttpAttributeRoutes();
//test
var json = config.Formatters.JsonFormatter;
json.SerializerSettings.PreserveReferencesHandling = Newtonsoft.Json.PreserveReferencesHandling.Objects;
config.Formatters.Remove(config.Formatters.XmlFormatter);
config.Routes.MapHttpRoute(
name: "DefaultApi",
// routeTemplate: "api/{controller}/{id}",
routeTemplate: "institute/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
//change xml to JSON output
// config.Formatters.JsonFormatter.SupportedMediaTypes.Add(new MediaTypeHeaderValue("text/html"));
}
}
}
StudentController.cs
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Web.Http;
using System.Web.Http.Description;
using WebAPI;
namespace WebAPI.Controllers
{
public class StudentsController : ApiController
{
private InstituteEntities db = new InstituteEntities();
// GET: api/Students
public IQueryable<Student> GetStudents()
{
return db.Students;
}
// GET: api/Students/5
[ResponseType(typeof(Student))]
public IHttpActionResult GetStudent(int id)
{
Student student = db.Students.Find(id);
if (student == null)
{
return NotFound();
}
return Ok(student);
}
// PUT: api/Students/5
[ResponseType(typeof(void))]
public IHttpActionResult PutStudent(int id, Student student)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
if (id != student.Id)
{
return BadRequest();
}
db.Entry(student).State = EntityState.Modified;
try
{
db.SaveChanges();
}
catch (DbUpdateConcurrencyException)
{
if (!StudentExists(id))
{
return NotFound();
}
else
{
throw;
}
}
return StatusCode(HttpStatusCode.NoContent);
}
// POST: api/Students
[ResponseType(typeof(Student))]
public IHttpActionResult PostStudent(Student student)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
db.Students.Add(student);
try
{
db.SaveChanges();
}
catch (DbUpdateException)
{
if (StudentExists(student.Id))
{
return Conflict();
}
else
{
throw;
}
}
return CreatedAtRoute("DefaultApi", new { id = student.Id }, student);
}
// DELETE: api/Students/5
[ResponseType(typeof(Student))]
public IHttpActionResult DeleteStudent(int id)
{
Student student = db.Students.Find(id);
if (student == null)
{
return NotFound();
}
db.Students.Remove(student);
db.SaveChanges();
return Ok(student);
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
db.Dispose();
}
base.Dispose(disposing);
}
private bool StudentExists(int id)
{
return db.Students.Count(e => e.Id == id) > 0;
}
}
}
のWeb.config
<?xml version="1.0" encoding="utf-8"?>
<!-- For more information on how to configure your ASP.NET application, please visit http://go.microsoft.com/fwlink/?LinkId=301879 -->
<configuration>
<configSections>
<!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
<section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
</configSections>
<appSettings></appSettings>
<system.web>
<compilation debug="true" targetFramework="4.5.2" />
<httpRuntime targetFramework="4.5.2" />
</system.web>
<system.webServer>
<modules runAllManagedModulesForAllRequests="true">
<remove name="WebDAVModule"/>
<!-- ADD THIS -->
</modules>
<handlers>
<remove name="ExtensionlessUrlHandler-Integrated-4.0" />
<remove name="OPTIONSVerbHandler" />
<remove name="TRACEVerbHandler" />
<add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
</handlers>
</system.webServer>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
</dependentAssembly>
</assemblyBinding>
</runtime>
<system.codedom>
<compilers>
<compiler language="c#;cs;csharp" extension=".cs" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:6 /nowarn:1659;1699;1701" />
<compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.VBCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:14 /nowarn:41008 /define:_MYTYPE=\"Web\" /optionInfer+" />
</compilers>
</system.codedom>
<connectionStrings>
<add name="InstituteEntities" connectionString="metadata=res://*/Institute.csdl|res://*/Institute.ssdl|res://*/Institute.msl;provider=System.Data.SqlClient;provider connection string="data source=BPWSVR01;initial catalog=Institute;persist security info=True;user id=sa;password=sa;MultipleActiveResultSets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
</connectionStrings>
<entityFramework>
<defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
<parameters>
<parameter value="mssqllocaldb" />
</parameters>
</defaultConnectionFactory>
<providers>
<provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
</providers>
</entityFramework>
</configuration>
私のエラーは以下の通りです：
{
"$id": "1",
"Message": "An error has occurred.",
"ExceptionMessage": "The 'ObjectContent`1' type failed to serialize the response body for content type 'application/json; charset=utf-8'.",
"ExceptionType": "System.InvalidOperationException",
"StackTrace": null,
"InnerException": {
"$id": "2",
"Message": "An error has occurred.",
"ExceptionMessage": "The ADO.NET provider with invariant name 'System.Data.SqlClient' is either not registered in the machine or application config file, or could not be loaded. See the inner exception for details.",
"ExceptionType": "System.ArgumentException",
"StackTrace":" at System.Data.Entity.Infrastructure.DependencyResolution.DefaultProviderFactoryResolver.<GetService>b__0(ArgumentException e, String n)
at System.Data.Entity.Infrastructure.DependencyResolution.DefaultProviderFactoryResolver.GetService(Type type, Object key, Func`3 handleFailedLookup)
at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
at System.Linq.Enumerable.WhereSelectArrayIterator`2.MoveNext()
at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
at System.Data.Entity.Infrastructure.DependencyResolution.RootDependencyResolver.GetService(Type type, Object key)
at System.Linq.Enumerable.WhereSelectArrayIterator`2.MoveNext()
at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
at System.Data.Entity.Infrastructure.DependencyResolution.CompositeResolver`2.GetService(Type type, Object key)
at System.Data.Entity.Infrastructure.DependencyResolution.DbDependencyResolverExtensions.GetService[T](IDbDependencyResolver resolver, Object key)
at System.Data.Entity.Core.EntityClient.EntityConnection.ChangeConnectionString(String newConnectionString)
at System.Data.Entity.Internal.LazyInternalConnection.InitializeFromConnectionStringSetting(ConnectionStringSettings appConfigConnection)
at System.Data.Entity.Internal.LazyInternalConnection.TryInitializeFromAppConfig(String name, AppConfig config)
at System.Data.Entity.Internal.LazyInternalConnection.Initialize()"
}
}
は、あなたのAPIメソッドを投稿し、私はあなたの問題を考えますシリアル化ではなく、代わりにエンティティフレームワークです。値を返す前にクエリを作成し、エラーが発生したかどうかを確認してください。 –
@ JGEstevez ..私はちょうどAPIを追加しました。 Plsは私が一見を助ける。おかげさまで 私はこのURLを使用して実行し、取得することができます。 ます。http：// localhostを：18289 /機関/学生 が、私はIIS上で展開した後： ます。http：// localhostの/ API /機関/学生 エラーが来ましたでる – coder