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Andrew Watson
Andrew Watson

Total Post:39

Posted on    December-11-2014 12:28 AM

 ASP.Net Database  SQL Server 

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I am working on a project which, up until today, has been fine. However now when I run it and it goes through a few different Stored Procedure calls it is throwing an InvalidOperationException with the message The connection was not closed. The connection's current state is open.


I get that I could put in a check to see if the connection is already open, but this code hasn't changed (it is under Version Control and isn't modified) so I'm looking for other potential explanations.


Could there be some lock in SQL which isn't being released? Is there a process which I should look out for and kill?


I can't really post the code as there is a lot of it, and it is split up into smaller methods which makes it harder to pull out individual items. E.g:


public SqlConnection Connection





        return _connection;




public IDataReader RetrieveRecord(int Id)



    SqlCommand cmd = this.Connection.CreateCommand();

cmd.CommandText = "SelectRecord";

    cmd.CommandType = CommandType.StoredProcedure;



    cmd.Parameters.Add(new SqlParameter("@tID", Id));


    //instruct the data reader to close its connection when its Close method is         called by passing the CommandBehavior.CloseConnection

    return cmd.ExecuteReader(CommandBehavior.CloseConnection);


Nothing massively complex, I just don't understand why this connection is now throwing an exception.

Chris S
Chris S

Total Post:48

Posted on    December-11-2014 6:31 AM

Problem is with the line



Because you are trying to open an already opened connection.


Try this to check before opening a connection:


 if (this._connection.State == ConnectionState.Closed)


Allen Scott

Total Post:41

Posted on    December-11-2014 7:01 AM

When you are talking about killing process, I think you know c# well.


You should always use








using(SqlConnection con=new SqlConnection("connectionString"))


  // Do something with con

     using(SqlCommand cmd=new SqlCommand("cmdText",con))


        // Do something with cmd



You know that SqlCommand and SqlConnection implement IDisposable

So when you put those objects within using, the connection closing and clean up job is automatically done.

No need to close the connection manually in the code, since using will do the work for you.

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