.Net core 3.1 Webapi Errors and Their Causes

 

 

Unable to resolve service for type 'SpProofOfConceptAPI.Dal.IEvaluationFormPartialDAL' while attempting to activate 'SpProofOfConceptAPI.Services.EvalDetailScores.EvalDetailScoresUpdateHandler'."} 

You forgot to declare this type SpProofOfConceptAPI.Dal.IEvaluationFormPartialDAL for IOC in the startup

Solution (and for the BLL cause you usually forget both)

             services.AddScoped<IEvaluationFormPartialDAL, EvaluationFormPartialDAL>();
            services.AddScoped<IEvaluationFormPartialBLL, EvaluationFormPartialBLL>();