第二个操作已开始

Question

当我开始我的页面时，一切都加载正常，我第二次尝试重新加载，我收到以下错误，我从角度运行网址

在上一个异步操作完成之前，在此上下文上启动了第二个操作。使用“await”确保在该上下文上调用另一个方法之前已完成任何异步操作。任何实例成员都不能保证线程安全。

这就是方法

    private readonly PuntovService  puntovService = new PuntovService(new PuntovRepository(CentralContext.Create()));
    private readonly IMapper mapper;

    public PuntovController()
    {
        this.mapper = WebApiApplication.MapperConfiguration.CreateMapper();
    }


    [HttpGet]
    [Route("Puntos")]
    [ResponseType(typeof(IEnumerable<PuntovDTO>))]
    public async Task<IHttpActionResult> GetAll()
    {
        var pv = await puntovService.GetAll();
        var puntovDTO = pv.Select(x =>  mapper.Map<PuntovDTO>(x));
        var tipoComitePersona = from com in puntovDTO
                                select  new {com.PuntoV};
        return Ok(tipoComitePersona);
    }

在这个类中，调用将成为数据库的上下文

using APICentralBL.Models;
using System.Data.Entity;

namespace APICentralBL.Data
{

    public  class CentralContext : DbContext
    {

        private static CentralContext centralContext = null;
        public CentralContext() : base("Context") 
        {
        
        }
        public DbSet<SDN> SDN {  get; set;}
        public DbSet<CALIF> CALIF { get; set; }
        public DbSet<UVT> UVT { get; set; }
        public DbSet<PUNTOV> PUNTOV { get; set; }
        public DbSet<TRANS> TRANS { get; set; }

        public static CentralContext Create()
        {
            if (centralContext == null)
                centralContext = new CentralContext();
              return centralContext;
        }
    }
}

这种情况不仅发生在这个方法中，当我尝试调用多个时也会发生

例如。StackTrace

   en System.Data.Entity.Internal.ThrowingMonitor.EnsureNotEntered()
   en System.Data.Entity.Core.Objects.ObjectQuery`1.System.Data.Entity.Infrastructure.IDbAsyncEnumerable<T>.GetAsyncEnumerator()
   en System.Data.Entity.Infrastructure.IDbAsyncEnumerableExtensions.ForEachAsync[T](IDbAsyncEnumerable`1 source, Action`1 action, CancellationToken cancellationToken)
   en System.Data.Entity.Infrastructure.IDbAsyncEnumerableExtensions.ToListAsync[T](IDbAsyncEnumerable`1 source, CancellationToken cancellationToken)
   en System.Data.Entity.Infrastructure.IDbAsyncEnumerableExtensions.ToListAsync[T](IDbAsyncEnumerable`1 source)
   en APICentralBL.Repositories.Implements.GenericRepository`1.<GetAll>d__3.MoveNext() en D:\ANTIOQUENA DEVELOPERS REPOSITORY\ANTIOQUENA DEVELOPERS\DEVELOPMENTS\API'S PROJECT\APICentral-Deploy\APICentralBL\Repositories\Implements\GenericRepository.cs: línea 33
   en System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   en System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   en System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   en APICentralBL.Services.Implements.GenericService`1.<GetAll>d__3.MoveNext() en D:\ANTIOQUENA DEVELOPERS REPOSITORY\ANTIOQUENA DEVELOPERS\DEVELOPMENTS\API'S PROJECT\APICentral-Deploy\APICentralBL\Services\Implements\GenericService.cs: línea 25
   en System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   en System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   en System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   en APICentral.Controllers.PuntovController.<GetAll>d__4.MoveNext() en D:\ANTIOQUENA DEVELOPERS REPOSITORY\ANTIOQUENA DEVELOPERS\DEVELOPMENTS\API'S PROJECT\APICentral-Deploy\APICentral\Controllers\PuntovController.cs: línea 65**

Answer 1

由于您的上下文存储在静态字段中，因此它将由同时向您的控制器提供请求的所有线程共享。您通常应该为每个请求使用上下文