我正在尝试调用 Web API Get 方法来获取数据，但我得到了这个异常::
{"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":{
"Message":"An error has occurred.",
"ExceptionMessage":"Error getting value from 'User' on 'System.Data.Entity.DynamicProxies.tblreferralService_D8499DD69BA2AEEF811721A9A453EE6BD1118C497BB3D8EF9C003F7EDEDC651E'.",
"ExceptionType":"Newtonsoft.Json.JsonSerializationException",
"StackTrace":" at Newtonsoft.Json.Serialization.DynamicValueProvider.GetValue(Object target)\r\n
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.CalculatePropertyValues(JsonWriter writer, Object value, JsonContainerContract contract, JsonProperty member, JsonProperty property, JsonContract& memberContract, Object& memberValue)\r\n
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeObject(JsonWriter writer, Object value, JsonObjectContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)\r\n
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue(JsonWriter writer, Object value, JsonContract valueContract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerProperty)\r\n
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeList(JsonWriter writer, IWrappedCollection values, JsonArrayContract contract, JsonProperty member, JsonContainerContract collectionContract, JsonProperty containerProperty)\r\n
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.SerializeValue(JsonWriter writer, Object value, JsonContract valueContract, JsonProperty member, JsonContainerContract containerContract, JsonProperty containerProperty)\r\n
at Newtonsoft.Json.Serialization.JsonSerializerInternalWriter.Serialize(JsonWriter jsonWriter, Object value)\r\n
at Newtonsoft.Json.JsonSerializer.SerializeInternal(JsonWriter jsonWriter, Object value)\r\n
at Newtonsoft.Json.JsonSerializer.Serialize(JsonWriter jsonWriter, Object value)\r\n
at System.Net.Http.Formatting.JsonMediaTypeFormatter.<>c__DisplayClassd.<WriteToStreamAsync>b__c()\r\n
at System.Threading.Tasks.TaskHelpers.RunSynchronously(Action action, CancellationToken token)",
"InnerException":{
"Message":"An error has occurred.",
"ExceptionMessage":"The ObjectContext instance has been disposed and can no longer be used for operations that require a connection.",
"ExceptionType":"System.ObjectDisposedException",
"StackTrace":" at System.Data.Objects.ObjectContext.EnsureConnection()\r\n
at System.Data.Objects.ObjectQuery`1.GetResults(Nullable`1 forMergeOption)\r\n
at System.Data.Objects.ObjectQuery`1.Execute(MergeOption mergeOption)\r\n
at System.Data.Objects.DataClasses.EntityReference`1.Load(MergeOption mergeOption)\r\n
at System.Data.Objects.DataClasses.RelatedEnd.Load()\r\n
at System.Data.Objects.DataClasses.RelatedEnd.DeferredLoad()\r\n
at System.Data.Objects.Internal.LazyLoadBehavior.LoadProperty[TItem](TItem propertyValue, String relationshipName, String targetRoleName, Boolean mustBeNull, Object wrapperObject)\r\n
at System.Data.Objects.Internal.LazyLoadBehavior.<>c__DisplayClass7`2.<GetInterceptorDelegate>b__2(TProxy proxy, TItem item)\r\n
at System.Data.Entity.DynamicProxies.tblreferralService_D8499DD69BA2AEEF811721A9A453EE6BD1118C497BB3D8EF9C003F7EDEDC651E.get_User()\r\n
at GetUser(Object )\r\n
at Newtonsoft.Json.Serialization.DynamicValueProvider.GetValue(Object target)"}}}
我经历了很多关于同一个异常的问题，但每个问题都有不相关的错误，这就是为什么我无法找出错误的正确原因并且它是修复。我也试过 这个
我将 Angularjs 工厂用于我所有的休息服务，即 Api 控制器。
这是我正在调用的视图和 API 控制器：
<script>
var demoApp = angular.module('demoApp', []);
demoApp.config(function ($routeProvider) {
$routeProvider.when('/', { controller: 'customersController', templateUrl: 'Home/List' })
.when('/Edit', { controller: 'customersController', templateUrl: 'Home/Edit' })
.otherwise({ redirectTo: '/' });
});
demoApp.factory('dataFactory', ['$http', function ($http) {
var urlBase = '/api/Customer';
var dataFactory = {};
dataFactory.getCustomers = function () {
return $http.get(urlBase);
};
dataFactory.getCustomer = function (id) {
return $http.get(urlBase + '/' + id);
};
return dataFactory;
}]);
demoApp.controller('customersController', ['$scope', 'dataFactory', function ($scope, dataFactory) {
$scope.status;
$scope.customers;
getCustomers();
function getCustomers() {
dataFactory.getCustomers()
.success(function (custs) {
$scope.customers = custs;
})
.error(function (error) {
$scope.status = 'Unable to load customer data: ' + error.message;
});
}
}]);
</script>
API 控制器
public class CustomerController : ApiController
{
//
// GET: /Customer/
public HttpResponseMessage Get()
{
CustomerService ObjService = new CustomerService();
var Clients = ObjService.GetClients();
if (Clients.Count < 1) throw new HttpResponseException(HttpStatusCode.NotFound);
return Request.CreateResponse<IEnumerable<tblreferralService>>(HttpStatusCode.OK, Clients);
}
// GET api/customers/5
public HttpResponseMessage Get(int id)
{
CustomerService ObjService = new CustomerService();
var Client = ObjService.GetClient(id);
if (Client == null) throw new HttpResponseException(HttpStatusCode.NotFound);
return Request.CreateResponse<tblreferralService>(HttpStatusCode.OK, Client);
}
}
WEBAPI。配置
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
config.Routes.MapHttpRoute(
name: "DefaultApi",
routeTemplate: "api/{controller}/{id}",
defaults: new { id = RouteParameter.Optional }
);
}
}
这就是我在控制台中的内容::
请指导我哪里错了。