我无法安装 system.net.http

Question

我在 .net 4.6.1 中有一个 web api 2 项目，我试图在其中添加自定义 ValidateModelAttribute 但我收到了 system.net.http 4.0 程序集的警告。

这是程序集属性

我曾多次尝试删除并重新安装该软件包，但我一直收到相同的警告。当我尝试使用 CustomModelAttribute 时，来自 Postman 的 api 调用会抛出以下错误

{

"Message": "An error has occurred.",

"ExceptionMessage": "Method not found: 'System.Net.Http.HttpRequestMessage System.Web.Http.Controllers.HttpActionContext.get_Request()'.",

"ExceptionType": "System.MissingMethodException",

"StackTrace": " at myapi.Api.Mvc.Filters.ValidateModelAttribute.OnActionExecuting(HttpActionContext actionContext)\r\n at System.Web.Http.Filters.ActionFilterAttribute.OnActionExecutingAsync(HttpActionContext actionContext, CancellationToken cancellationToken)\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Filters.ActionFilterAttribute.d__0.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Controllers.ActionFilterResult.d__2.MoveNext()\r\n--- End of stack trace from previous location where exception was thrown ---\r\n at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)\r\n at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)\r\n at System.Web.Http.Dispatcher.HttpControllerDispatcher.d__1.MoveNext()" }

这是自定义属性

using System.Net;
using System.Web.Http.Controllers;
using System.Net.Http;
using System.Web.Http.Filters;

namespace myapi.Api.Mvc.Filters
{
    public class ValidateModelAttribute : ActionFilterAttribute
    {
        public override void OnActionExecuting(HttpActionContext actionContext)
        {
            if (actionContext.ModelState.IsValid == false)
            {
                actionContext.Response = actionContext.Request.CreateErrorResponse(
                    HttpStatusCode.BadRequest, actionContext.ModelState);
            }
        }
    }
}

Answer 1

我终于让它工作了。我所要做的就是右键单击 system.net.http 程序集并单击属性。然后我将 copy local 设置为 true

我无法安装 system.net.http

I can't install system.net.http

c#

system.net