Question

ExecuteNonQuery requires an open and available Connection. The connection’s current state is closed.

What am I doing wrong here? I’m assuming you can reuse the connection?

Thanks for any help!

using (SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["LocalSqlServer"].ToString()))
{
    cn.Open();

    // If we are reverting to an old type
    if (pageAction == "revert")
    {
        debug.Text = "FLAG 1";

        // Get the revert ID
        int revertingID = int.Parse(Request.QueryString["revID"]);
        bool rowsReturned = false;

        debug.Text = "FLAG 2 - " + revertingID.ToString();

        // Set all to 0
        using (SqlCommand cmd = new SqlCommand("SELECT ID FROM tblSiteSettings WHERE ID = " + revertingID, cn))
        {
            // If it exists
            SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
            if (rdr.Read())
            {
                rowsReturned = true;
            }
            rdr.Close();
        }

        debug.Text = "FLAG 3 - " + rowsReturned.ToString();

        // Set new active and reset others
        if (rowsReturned == true)
        {
            using (SqlCommand cmd = new SqlCommand("UPDATE tblSiteSettings SET isActive = 1 WHERE ID = " + revertingID, cn))
            {
                cmd.ExecuteNonQuery();
            }
            using (SqlCommand cmd = new SqlCommand("UPDATE tblSiteSettings SET isActive = 0 WHERE ID <> " + revertingID, cn))
            {
                cmd.ExecuteNonQuery();
            }
        }
        //debug.Text = "FLAG 4 - ";
    }

Answer 1

Your problem is:

SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);

You should just call cmd.ExecuteReader()' if you want to use the connection again prior to "getting rid" of it. If you want to get an understanding for what the CommandBehaviour.CloseConnection part does/means then the documentation for SqlCommand.ExecuteReader is a good bet. There’s also documentation to tell you what all the possible values of the CommandBehaviour enumeration are. Essentially CommandBehaviour.CloseConnection does the following:

When the command is executed, the associated Connection object is closed when the associated DataReader object is closed.

If you have no special need to specify a CommandBehaviour, then either specify CommandBehaviour.Default, or don’t specify one at all. CommandBehaviour.Default is:

The query may return multiple result sets. Execution of the query may affect the database state. Default sets no CommandBehavior flags, so calling ExecuteReader(CommandBehavior.Default) is functionally equivalent to calling ExecuteReader().