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 140:           // SqlCommand cmd = new SqlCommand("select * from tbl_courses where CourseTitle='" + Request.QueryString["CourseTitle"].ToString() + "' ", con);
Line 141:
Line 142:            SqlCommand cmd = new SqlCommand("select * from tbl_courses where Subject='" + Request.QueryString["subject"].ToString() + "' and Active='Yes'", con);
Line 143:
Line 144:            cmd.CommandType = CommandType.Text;

Source File: c:\inetpub\wwwroot\stanmore\stanmoreuk.org\diploma.aspx.cs    Line: 142

Stack Trace:


[NullReferenceException: Object reference not set to an instance of an object.]
   course4.Showdata() in c:\inetpub\wwwroot\stanmore\stanmoreuk.org\diploma.aspx.cs:142
   course4.Page_Load(Object sender, EventArgs e) in c:\inetpub\wwwroot\stanmore\stanmoreuk.org\diploma.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:4.8.4110.0