Question

I have developed WCF service which is internally using Entity framework for Database operation. While Insert, Update and Delete is working fine I am facing issue while selection of all records from that table and exposing it to client.

My Code to Expose Data to client is :-

public IQueryable <Bank_Configuration>  SelectBankConfiguration()
        {
            using (EFEntities objEFEntities = new EFEntities())
            {                             
                var Result= from c in objEFEntities.Bank_Configuration 
                            select c;

                return Result;
            }            

        }

But at client end when I use this method to get data client is giving Error as
An error occurred while receiving the HTTP response to “http://localhost:8732/Design_Time_Addresses/WcfServiceLibrary1/Service1/.” This could be due to the service endpoint binding not using the HTTP protocol. This could also be due to an HTTP request context being aborted by the server (possibly due to the service shutting down). See server logs for more details.

Why this error and how to expose data to client

Answer 1

Your EFEntities object is being disposed before the WCF message is being serialized, which is what causes the EF query to actually execute. Matierialize your resultset inside the “using” block by calling ToList() or ToArray().

public IEnumerable<Bank_Configuration>  SelectBankConfiguration()
{
    using (EFEntities objEFEntities = new EFEntities())
    {                             
        var Result= from c in objEFEntities.Bank_Configuration 
                    select c;

        return Result.ToArray();
    }            

}