Objektreferenz wird nicht auf eine Instanz eines Objekts gesetzt, wenn Autorisierung mit Rollen verwendet wird

Question

Ich versuche, Aspnet mit Rollen zu verwenden. Mit der NRE kann ich immer noch nicht herausfinden, was zu instantiieren ist. Dies ist in der Steuerung

[Authorize(Roles = "Admin")] 
public ActionResult ForAdmin() 
{ 
    return View(); 
} 

Dies ist, wie ich

public Programmer GetLoginCredentials(Login credential) 
{ 
    Programmer programmer = null; 
    HttpContext.Current.Session["ProgrammerName"] = null; 
    HttpContext.Current.Session["Roles"] = null; 
    using (
     var cmd = new SqlCommand("Sp_GetLoginCredentials", _dbConnection) 
     { 
      CommandType = CommandType.StoredProcedure 
     }) 
    { 
     try 
     { 
      cmd.Parameters.AddWithValue("@Username", credential.Username); 
      cmd.Parameters.AddWithValue("@Password", credential.Password); 
      var da = new SqlDataAdapter(cmd); 
      var ds = new DataSet(); 
      da.Fill(ds); 

      if (ds.Tables[0].Rows.Count <= 0) return null; 
      foreach (DataRow row in ds.Tables[0].Rows) 
      { 
       programmer = new Programmer() 
       { 
        ProgrammerId = Convert.ToInt32(row["ProgrammerId"]), 
        ProgrammerName = row["ProgrammerName"].ToString(), 
        Username = row["Username"].ToString(), 
        Password = row["Password"].ToString() 
       }; 

       HttpContext.Current.Session["ProgrammerName"] = programmer.ProgrammerName; 
      } 
      if (programmer != null) 
      { 
       GetRoles(programmer); 
      } 

      return programmer; 
     } 
     catch 
     { 
      return null; 
     } 
    } 
} 

autorisieren Dies ist, wie ich die Sitzung mit Rollen

public List<Role> GetRoles(Programmer credential) 
{ 
    var roleList = new List<Role>(); 
    using (var cmd = new SqlCommand("Sp_GetRoles", _dbConnection) {CommandType = CommandType.StoredProcedure}) 
    { 
     cmd.Parameters.AddWithValue("@Username", credential.Username); 
     cmd.Parameters.AddWithValue("@Password", credential.Password); 

     var da = new SqlDataAdapter(cmd); 
     var ds = new DataSet(); 
     da.Fill(ds); 

     if (ds.Tables[0].Rows.Count > 0) 
     { 
      roleList.AddRange(from DataRow row in ds.Tables[0].Rows 
       select new Role() 
       { 
        RoleName = row["RoleName"].ToString() 
       }); 
     } 
     HttpContext.Current.Session["Roles"] = roleList; 
    } 
    return roleList; 
} 

Diese füllen ist mein Rollenanbieter

public class SiteRole : RoleProvider 
{ 
    public override string[] GetRolesForUser(string username) 
    { 
     var data = HttpContext.Current.Session["Roles"]; 
     return data as string[]; 
    } 
} 

In meiner Session [ „Rollen“] ich es wie diese

Das heißt also, ich bin in der Lage, die „Admin“ Rolle zu bekommen, aber in meinem Browser, bekomme ich diesen Fehler:

[NullReferenceException: Object reference not set to an instance of an object.] 
    System.Web.Security.RolePrincipal.IsInRole(String role) +9803940 
    System.Linq.Enumerable.Any(IEnumerable`1 source, Func`2 predicate) +146 
    System.Web.Mvc.AuthorizeAttribute.AuthorizeCore(HttpContextBase httpContext) +333 
    System.Web.Mvc.AuthorizeAttribute.OnAuthorization(AuthorizationContext filterContext) +379 
    System.Web.Mvc.ControllerActionInvoker.InvokeAuthorizationFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor) +143 
    System.Web.Mvc.Async.<>c__DisplayClass21.<BeginInvokeAction>b__19(AsyncCallback asyncCallback, Object asyncState) +1680 
    System.Web.Mvc.Async.WrappedAsyncResult`1.CallBeginDelegate(AsyncCallback callback, Object callbackState) +59 
    System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +151 
    System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object state, BeginInvokeDelegate beginDelegate, EndInvokeDelegate`1 endDelegate, Object tag, Int32 timeout) +94 
    System.Web.Mvc.Async.AsyncControllerActionInvoker.BeginInvokeAction(ControllerContext controllerContext, String actionName, AsyncCallback callback, Object state) +559 
    System.Web.Mvc.Controller.<BeginExecuteCore>b__1c(AsyncCallback asyncCallback, Object asyncState, ExecuteCoreState innerState) +82 
    System.Web.Mvc.Async.WrappedAsyncVoid`1.CallBeginDelegate(AsyncCallback callback, Object callbackState) +73 
    System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +151 
    System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object callbackState, BeginInvokeDelegate`1 beginDelegate, EndInvokeVoidDelegate`1 endDelegate, TState invokeState, Object tag, Int32 timeout, SynchronizationContext callbackSyncContext) +105 
    System.Web.Mvc.Controller.BeginExecuteCore(AsyncCallback callback, Object state) +588 
    System.Web.Mvc.Controller.<BeginExecute>b__14(AsyncCallback asyncCallback, Object callbackState, Controller controller) +47 
    System.Web.Mvc.Async.WrappedAsyncVoid`1.CallBeginDelegate(AsyncCallback callback, Object callbackState) +65 
    System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +151 
    System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object callbackState, BeginInvokeDelegate`1 beginDelegate, EndInvokeVoidDelegate`1 endDelegate, TState invokeState, Object tag, Int32 timeout, SynchronizationContext callbackSyncContext) +139 
    System.Web.Mvc.Controller.BeginExecute(RequestContext requestContext, AsyncCallback callback, Object state) +484 
    System.Web.Mvc.Controller.System.Web.Mvc.Async.IAsyncController.BeginExecute(RequestContext requestContext, AsyncCallback callback, Object state) +50 
    System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__4(AsyncCallback asyncCallback, Object asyncState, ProcessRequestState innerState) +98 
    System.Web.Mvc.Async.WrappedAsyncVoid`1.CallBeginDelegate(AsyncCallback callback, Object callbackState) +73 
    System.Web.Mvc.Async.WrappedAsyncResultBase`1.Begin(AsyncCallback callback, Object state, Int32 timeout) +151 
    System.Web.Mvc.Async.AsyncResultWrapper.Begin(AsyncCallback callback, Object callbackState, BeginInvokeDelegate`1 beginDelegate, EndInvokeVoidDelegate`1 endDelegate, TState invokeState, Object tag, Int32 timeout, SynchronizationContext callbackSyncContext) +106 
    System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, Object state) +446 
    System.Web.Mvc.MvcHandler.BeginProcessRequest(HttpContext httpContext, AsyncCallback callback, Object state) +88 
    System.Web.Mvc.MvcHandler.System.Web.IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, Object extraData) +50 
    System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +103 
    System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155 

Kannst du mir bitte zeigen, wo ich falsch liege? Vielen Dank.

Answer 1

Sie können nicht HttpContext.Current.Session["Roles"]-string[] werfen, weil es vom Typ ist List<Role>

dies stattdessen versuchen:

public override string[] GetRolesForUser(string username) 
{ 
    var data = HttpContext.Current.Session["Roles"] as IEnumerable<Role>; 
    return data.Select(d => d.RoleName).ToArray(); 
}