System.NullReferenceException: Object reference not set to an instance of an object. at Goworkla.MainSite.Controllers.AirMilkroundController.AirMilkroundDetail(String mrid, String collegeid, String mrnumberid) in C:\0Work\Codes\Mapping\mainsite\src\Goworkla.MainSite\Goworkla.MainSite\Controllers\AirMilkroundController.cs:line 46 at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.TaskOfIActionResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments) at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.g__Awaited|12_0(ControllerActionInvoker invoker, ValueTask`1 actionResultValueTask) at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted) at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context) at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted) at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.g__Awaited|13_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted) at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|24_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted) at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context) at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted) at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|19_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted) at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope) at Microsoft.AspNetCore.Routing.EndpointMiddleware.g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger) at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context) at Goworkla.MainSite.MiddleWare.ErrorMiddleware.Invoke(HttpContext context) in C:\0Work\Codes\Mapping\mainsite\src\Goworkla.MainSite\Goworkla.MainSite\MiddleWare\ErrorMiddleware.cs:line 31 at Microsoft.AspNetCore.ResponseCaching.ResponseCachingMiddleware.Invoke(HttpContext httpContext) at Goworkla.MainSite.MiddleWare.RequesterFilter.Invoke(HttpContext context) in C:\0Work\Codes\Mapping\mainsite\src\Goworkla.MainSite\Goworkla.MainSite\MiddleWare\RequesterFilter.cs:line 39 at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context) HEADERS ======= Accept: */* Connection: keep-alive Host: www.goworkla.cn Referer: https://goworkla.cn/AirMilkround/AirMilkroundDetail?mrid=5f6abb8ec6234741b067a304&collegeid=5e6b3b5595017e12c0b58329 User-Agent: claudebot 8e7f1b72cbb70c2b9a0b62ddac52bb21: tag X-Forwarded-For: 54.173.214.79 X-Lego-Via: 200488 X-Forwarded-Proto: https Tencent-Acceleration-Domain-Name: www.goworkla.cn 0b23b94ddee82eff071751c6a577a12a: tag X-NWS-LOG-UUID: 14749857836944176894 eaac1b80b890f73995aa62bcaeff59e8: tag X-Tencent-Ua: Qcloud