(ASP.NET Core Razor Pages) Unable to access Session Variables from other pages











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I am trying to access some Session Variables in a Razor Pages application, but am met with NullReferenceException errors.



Currently, I set the variables in a method in the model associated with a "user login" page:



public void StoreUserData(string username, string name, int accesslevel)
{
HttpContext.Session.SetString("username", username);
HttpContext.Session.SetString("name", name);
HttpContext.Session.SetInt32("accesslevel", accesslevel);
}


I then call this method (and the method which gets the data to be stored) when the user submits the login form on the page (on post):



public IActionResult OnPost()
{
(string username, string name, int accesslevel) = Login();
StoreUserData(username, name, accesslevel);
ViewData["username"] = HttpContext.Session.GetString("username");
return Page();
}


I know that the session variables are being saved, and can be accessed (at least on the "login" page) because the "username" string is correctly displayed on the page using ViewData, as shown in the block above.



When I try to access the same session variables in another razor page, it doesn't work.



I want to check the session variables when the page loads. C# method (part of page model for second page):



public (string username, string name, int accesslevel) GetUserData()
{
string username = HttpContext.Session.GetString("username");
string name = HttpContext.Session.GetString("name");
int accesslevel = Convert.ToInt32(HttpContext.Session.GetInt32("accesslevel"));

return (username, name, accesslevel);
}


And C# block on html page to call this method (I don't know a better way to do this when the page loads):



@{ 
Test_1Model model = new Test_1Model();
(string username, string name, int accesslevel) = model.GetUserData();
<div>@username</div>
}


At the moment, I just want to display one of the session variables on this second page to check everything's working.



Finally, in startup.cs:
Configure Services:



public void ConfigureServices(IServiceCollection services)
{
services.AddSession(options =>
{
options.IdleTimeout = TimeSpan.FromMinutes(10);
});

services.AddHttpContextAccessor();

services.AddMemoryCache();

services.AddMvc();
services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
}


Configure:



public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
app.UseStaticFiles();
app.UseSession();
app.UseMvc(routes =>
{
routes.MapRoute(
name: "default",
template: "{controller=Home}/{action=Index}/{id?}");
});


I know it's a lot of information, but I've tried to be as thorough as possible. Any help is greatly appreciated.










share|improve this question


























    up vote
    2
    down vote

    favorite












    I am trying to access some Session Variables in a Razor Pages application, but am met with NullReferenceException errors.



    Currently, I set the variables in a method in the model associated with a "user login" page:



    public void StoreUserData(string username, string name, int accesslevel)
    {
    HttpContext.Session.SetString("username", username);
    HttpContext.Session.SetString("name", name);
    HttpContext.Session.SetInt32("accesslevel", accesslevel);
    }


    I then call this method (and the method which gets the data to be stored) when the user submits the login form on the page (on post):



    public IActionResult OnPost()
    {
    (string username, string name, int accesslevel) = Login();
    StoreUserData(username, name, accesslevel);
    ViewData["username"] = HttpContext.Session.GetString("username");
    return Page();
    }


    I know that the session variables are being saved, and can be accessed (at least on the "login" page) because the "username" string is correctly displayed on the page using ViewData, as shown in the block above.



    When I try to access the same session variables in another razor page, it doesn't work.



    I want to check the session variables when the page loads. C# method (part of page model for second page):



    public (string username, string name, int accesslevel) GetUserData()
    {
    string username = HttpContext.Session.GetString("username");
    string name = HttpContext.Session.GetString("name");
    int accesslevel = Convert.ToInt32(HttpContext.Session.GetInt32("accesslevel"));

    return (username, name, accesslevel);
    }


    And C# block on html page to call this method (I don't know a better way to do this when the page loads):



    @{ 
    Test_1Model model = new Test_1Model();
    (string username, string name, int accesslevel) = model.GetUserData();
    <div>@username</div>
    }


    At the moment, I just want to display one of the session variables on this second page to check everything's working.



    Finally, in startup.cs:
    Configure Services:



    public void ConfigureServices(IServiceCollection services)
    {
    services.AddSession(options =>
    {
    options.IdleTimeout = TimeSpan.FromMinutes(10);
    });

    services.AddHttpContextAccessor();

    services.AddMemoryCache();

    services.AddMvc();
    services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
    }


    Configure:



    public void Configure(IApplicationBuilder app, IHostingEnvironment env)
    {
    app.UseStaticFiles();
    app.UseSession();
    app.UseMvc(routes =>
    {
    routes.MapRoute(
    name: "default",
    template: "{controller=Home}/{action=Index}/{id?}");
    });


    I know it's a lot of information, but I've tried to be as thorough as possible. Any help is greatly appreciated.










    share|improve this question
























      up vote
      2
      down vote

      favorite









      up vote
      2
      down vote

      favorite











      I am trying to access some Session Variables in a Razor Pages application, but am met with NullReferenceException errors.



      Currently, I set the variables in a method in the model associated with a "user login" page:



      public void StoreUserData(string username, string name, int accesslevel)
      {
      HttpContext.Session.SetString("username", username);
      HttpContext.Session.SetString("name", name);
      HttpContext.Session.SetInt32("accesslevel", accesslevel);
      }


      I then call this method (and the method which gets the data to be stored) when the user submits the login form on the page (on post):



      public IActionResult OnPost()
      {
      (string username, string name, int accesslevel) = Login();
      StoreUserData(username, name, accesslevel);
      ViewData["username"] = HttpContext.Session.GetString("username");
      return Page();
      }


      I know that the session variables are being saved, and can be accessed (at least on the "login" page) because the "username" string is correctly displayed on the page using ViewData, as shown in the block above.



      When I try to access the same session variables in another razor page, it doesn't work.



      I want to check the session variables when the page loads. C# method (part of page model for second page):



      public (string username, string name, int accesslevel) GetUserData()
      {
      string username = HttpContext.Session.GetString("username");
      string name = HttpContext.Session.GetString("name");
      int accesslevel = Convert.ToInt32(HttpContext.Session.GetInt32("accesslevel"));

      return (username, name, accesslevel);
      }


      And C# block on html page to call this method (I don't know a better way to do this when the page loads):



      @{ 
      Test_1Model model = new Test_1Model();
      (string username, string name, int accesslevel) = model.GetUserData();
      <div>@username</div>
      }


      At the moment, I just want to display one of the session variables on this second page to check everything's working.



      Finally, in startup.cs:
      Configure Services:



      public void ConfigureServices(IServiceCollection services)
      {
      services.AddSession(options =>
      {
      options.IdleTimeout = TimeSpan.FromMinutes(10);
      });

      services.AddHttpContextAccessor();

      services.AddMemoryCache();

      services.AddMvc();
      services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
      }


      Configure:



      public void Configure(IApplicationBuilder app, IHostingEnvironment env)
      {
      app.UseStaticFiles();
      app.UseSession();
      app.UseMvc(routes =>
      {
      routes.MapRoute(
      name: "default",
      template: "{controller=Home}/{action=Index}/{id?}");
      });


      I know it's a lot of information, but I've tried to be as thorough as possible. Any help is greatly appreciated.










      share|improve this question













      I am trying to access some Session Variables in a Razor Pages application, but am met with NullReferenceException errors.



      Currently, I set the variables in a method in the model associated with a "user login" page:



      public void StoreUserData(string username, string name, int accesslevel)
      {
      HttpContext.Session.SetString("username", username);
      HttpContext.Session.SetString("name", name);
      HttpContext.Session.SetInt32("accesslevel", accesslevel);
      }


      I then call this method (and the method which gets the data to be stored) when the user submits the login form on the page (on post):



      public IActionResult OnPost()
      {
      (string username, string name, int accesslevel) = Login();
      StoreUserData(username, name, accesslevel);
      ViewData["username"] = HttpContext.Session.GetString("username");
      return Page();
      }


      I know that the session variables are being saved, and can be accessed (at least on the "login" page) because the "username" string is correctly displayed on the page using ViewData, as shown in the block above.



      When I try to access the same session variables in another razor page, it doesn't work.



      I want to check the session variables when the page loads. C# method (part of page model for second page):



      public (string username, string name, int accesslevel) GetUserData()
      {
      string username = HttpContext.Session.GetString("username");
      string name = HttpContext.Session.GetString("name");
      int accesslevel = Convert.ToInt32(HttpContext.Session.GetInt32("accesslevel"));

      return (username, name, accesslevel);
      }


      And C# block on html page to call this method (I don't know a better way to do this when the page loads):



      @{ 
      Test_1Model model = new Test_1Model();
      (string username, string name, int accesslevel) = model.GetUserData();
      <div>@username</div>
      }


      At the moment, I just want to display one of the session variables on this second page to check everything's working.



      Finally, in startup.cs:
      Configure Services:



      public void ConfigureServices(IServiceCollection services)
      {
      services.AddSession(options =>
      {
      options.IdleTimeout = TimeSpan.FromMinutes(10);
      });

      services.AddHttpContextAccessor();

      services.AddMemoryCache();

      services.AddMvc();
      services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
      }


      Configure:



      public void Configure(IApplicationBuilder app, IHostingEnvironment env)
      {
      app.UseStaticFiles();
      app.UseSession();
      app.UseMvc(routes =>
      {
      routes.MapRoute(
      name: "default",
      template: "{controller=Home}/{action=Index}/{id?}");
      });


      I know it's a lot of information, but I've tried to be as thorough as possible. Any help is greatly appreciated.







      asp.net-core session-variables nullreferenceexception razor-pages session-storage






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Nov 22 at 16:07









      bbbb

      373




      373
























          1 Answer
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          up vote
          1
          down vote



          accepted










          This is caused by that Test_1Model model = new Test_1Model();, you should use Model instead of initializing a new Test_1Model. For this new object, it is not related with your request, it's just an object.



          Try.



          @{
          ViewData["Title"] = "Contact";
          //ContactModel model = new ContactModel();
          (string username, string name, int accesslevel) = Model.GetUserData();
          <div>@username</div>
          }





          share|improve this answer





















          • It works! Thank you very much
            – bbbb
            Nov 23 at 8:24











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          1 Answer
          1






          active

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          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

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          active

          oldest

          votes








          up vote
          1
          down vote



          accepted










          This is caused by that Test_1Model model = new Test_1Model();, you should use Model instead of initializing a new Test_1Model. For this new object, it is not related with your request, it's just an object.



          Try.



          @{
          ViewData["Title"] = "Contact";
          //ContactModel model = new ContactModel();
          (string username, string name, int accesslevel) = Model.GetUserData();
          <div>@username</div>
          }





          share|improve this answer





















          • It works! Thank you very much
            – bbbb
            Nov 23 at 8:24















          up vote
          1
          down vote



          accepted










          This is caused by that Test_1Model model = new Test_1Model();, you should use Model instead of initializing a new Test_1Model. For this new object, it is not related with your request, it's just an object.



          Try.



          @{
          ViewData["Title"] = "Contact";
          //ContactModel model = new ContactModel();
          (string username, string name, int accesslevel) = Model.GetUserData();
          <div>@username</div>
          }





          share|improve this answer





















          • It works! Thank you very much
            – bbbb
            Nov 23 at 8:24













          up vote
          1
          down vote



          accepted







          up vote
          1
          down vote



          accepted






          This is caused by that Test_1Model model = new Test_1Model();, you should use Model instead of initializing a new Test_1Model. For this new object, it is not related with your request, it's just an object.



          Try.



          @{
          ViewData["Title"] = "Contact";
          //ContactModel model = new ContactModel();
          (string username, string name, int accesslevel) = Model.GetUserData();
          <div>@username</div>
          }





          share|improve this answer












          This is caused by that Test_1Model model = new Test_1Model();, you should use Model instead of initializing a new Test_1Model. For this new object, it is not related with your request, it's just an object.



          Try.



          @{
          ViewData["Title"] = "Contact";
          //ContactModel model = new ContactModel();
          (string username, string name, int accesslevel) = Model.GetUserData();
          <div>@username</div>
          }






          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered Nov 23 at 7:12









          Tao Zhou

          4,34021028




          4,34021028












          • It works! Thank you very much
            – bbbb
            Nov 23 at 8:24


















          • It works! Thank you very much
            – bbbb
            Nov 23 at 8:24
















          It works! Thank you very much
          – bbbb
          Nov 23 at 8:24




          It works! Thank you very much
          – bbbb
          Nov 23 at 8:24


















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