Server Error in '/' Application.

Object reference not set to an instance of an object.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:


Line 32:         int id = Request.QueryString["id"].getInt32();
Line 33:         Courses course = new CourseService().GetOne(id);
Line 34:         List<CourseUsersRegister> lstcourse = new CourseUsersRegisterService().GetAll(course.ID).Where(m=>m.IsConfirm==true).ToList();
Line 35:         if (course != null)
Line 36:         {

Source File: d:\websites\arashalpineclub.ir\httpdocs\CourseDetail.aspx.cs    Line: 34

Stack Trace:


[NullReferenceException: Object reference not set to an instance of an object.]
   CourseDetail.bind() in d:\websites\arashalpineclub.ir\httpdocs\CourseDetail.aspx.cs:34
   CourseDetail.Page_Load(Object sender, EventArgs e) in d:\websites\arashalpineclub.ir\httpdocs\CourseDetail.aspx.cs:25
   System.Web.UI.Control.OnLoad(EventArgs e) +107
   System.Web.UI.Control.LoadRecursive() +89
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1532


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.8.4682.0