我有2条政策：Readers和Writers。 对于每一项政策，我都会拥有许多属于它们的值：

Readers: [1,2,3,4,5,6]
Writers: [100,400,500]

此数组将存储在数据库中，或者通过Http调用进行检索。

我该如何代替某些示例中的预定义值来检查所需的索赔值：

 services.AddAuthorization(options =>
        {
               options.AddPolicy("Readers",policy =>policy.Requireclaim("UserID","1","2","3","4","5"));
        });

得到这样的东西：

 CheckPolicyService someService;
 services.AddAuthorization(options =>
            {
                options.AddPolicy("Readers",async (userId)=>await someService.CheckClaimAsync(new Claim("UserID",userId,),"Readers"));
            });

我该如何代替检查EmployerID是否在给定值列表中，而是致电服务 检查这个吗？

public class PolicyRepo
{
   public string PolicyID{get;set;}
   public string[] Users{get;set;}
}

public class CheckPolicyService
{
  private PolicyRepo [] repos {get;set;} //all policies with their allowed users
  public async Task<bool> CheckClaimAsync(Claim userClaim,string policy)
  {
      if(userClaim.Type!="UserID")
      {
         return false;
      }
      bool hasaccess=this.repos.Single(r=>r.PolicyId==policy).Users.Contains(userClaim.Value);
      return hasaccess;

  }
}


public class Controller 
{
   [Authorize(Policy="Readers")]
   public async Task ReadAsync()
   {

   }
   [Authorize(Policy="Writers")]
   public async Task WriteAsync()
   {
   }
}