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 25:         SqlCommand cmd = new SqlCommand();
Line 26:         cmd.Connection = con;
Line 27:         string sql = "select sum (gheimatkol) from TblForosh where idshakhs=" + Request.Cookies["idShakhs"].Value.ToString();
Line 28:         cmd.CommandText = sql;
Line 29:         con.Open();

Source File: c:\vhosts\baratel.ir\httpdocs\card.aspx.cs    Line: 27

Stack Trace:


[NullReferenceException: Object reference not set to an instance of an object.]
   card.Page_Load(Object sender, EventArgs e) in c:\vhosts\baratel.ir\httpdocs\card.aspx.cs:27
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +51
   System.Web.UI.Control.OnLoad(EventArgs e) +95
   System.Web.UI.Control.LoadRecursive() +59
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +678


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.7.3650.0