There is already an open datareader associated with this command which must be closed first.

Question

0.00/5 (No votes)

See more:

C#

<pre> if (e.CommandName == "DoPlus")//Check quantity here
        {
            string PID = (e.CommandArgument.ToString());
            using (SqlConnection con = new SqlConnection(CS))
            {
                SqlCommand cmd = new SqlCommand("SP_getUserCartItem", con)
                {
                    CommandType = CommandType.StoredProcedure
                };
                cmd.Parameters.AddWithValue("@PID", PID);
                cmd.Parameters.AddWithValue("@UserID", UserID);
                using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
                {
                    DataTable dt = new DataTable();
                    sda.Fill(dt);

                    if (con.State == ConnectionState.Closed)
                    {
                        con.Open();
                        using (SqlDataReader dr = cmd.ExecuteReader())
                        {
                            if (dt.Rows.Count > 0)
                            {
                                Int32 myQty = Convert.ToInt32(dt.Rows[0]["Qty"].ToString());
                                while (dr.Read())
                                {
                                    int PQuantity = Convert.ToInt32(dr["PQuantity"].ToString());
                                    
                                    if (myQty < PQuantity)
                                    {
                                        Int32 updateQty = Convert.ToInt32(dt.Rows[0]["Qty"].ToString());
                                        SqlCommand myCmd = new SqlCommand("SP_UpdateCart", con)
                                        {
                                            CommandType = CommandType.StoredProcedure
                                        };
                                        myCmd.Parameters.AddWithValue("@Quantity", updateQty + 1);
                                        myCmd.Parameters.AddWithValue("@CartPID", PID);
                                        myCmd.Parameters.AddWithValue("@UserID", UserID);
                                       
                                        Int64 CartID = Convert.ToInt64(myCmd.ExecuteNonQuery());
                                      
                                        con.Close();
                                        BindProductCart();
                                        BindCartNumber();
                                    }


                                    else if (myQty > PQuantity)//check quantity between tblCart and tblProducts
                                    {
                                        divQtyError2.Visible = true;


                                    }

                                }dr.Close();

                            }
                           
                        }
                    } 
                }con.Close();
            }
        }

What I have tried:

At first i got error message

The connection was not closed. The connection's current state is open.

But when i exclude con.open(); before

Int64 CartID = Convert.ToInt64(myCmd.ExecuteNonQuery());

and con.Close(); after that code, I got this error.

Posted 15-Mar-21 0:02am

Member 15100384

Updated 15-Mar-21 3:04am

Add a Solution

Comments

Richard MacCutchan 15-Mar-21 6:46am

Why are you trying to use a data reader when you have already read the result set into your data adapter?

2 solutions

Solution 1

You don't need to call Close on anything if you're using using.

Try removing those and see what happens.

Also, you can't re-use a SqlParameter list. You have to clear it out and re-add the parameters.

Posted 15-Mar-21 1:51am

#realJSOP

Updated 15-Mar-21 1:53am

v2

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard Deeming · Accepted Answer · 2021-03-15T03:04:00

Your code is rather confused. You load the results of the stored procedure into a DataTable, then execute the command again and read through the results you've already loaded one at a time.

The error is thrown because you have an active SqlDataReader reading rows from the connection, and you're trying to execute another command on the same connection.

Since you've already loaded the rows, you don't need the data reader at all.

C#

if (e.CommandName == "DoPlus")//Check quantity here
{
    string PID = e.CommandArgument.ToString();
    
    using (SqlConnection con = new SqlConnection(CS))
    using (SqlCommand cmd = new SqlCommand("SP_getUserCartItem", con) { CommandType = CommandType.StoredProcedure })
    {
        cmd.Parameters.AddWithValue("@PID", PID);
        cmd.Parameters.AddWithValue("@UserID", UserID);
        
        con.Open();

        DataTable dt = new DataTable();
        using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
        {
            sda.Fill(dt);
        }
        
        foreach (DataRow row in dt.Rows)
        {
            int myQty = row.Field<int>("Qty");
            int PQuantity = row.Field<int>("PQuantity");
            if (myQty < PQuantity)
            {
                int updateQty = row.Field<int>("Qty");
                
                using (SqlCommand myCmd = new SqlCommand("SP_UpdateCart", con) { CommandType = CommandType.StoredProcedure })
                {
                    myCmd.Parameters.AddWithValue("@Quantity", updateQty + 1);
                    myCmd.Parameters.AddWithValue("@CartPID", PID);
                    myCmd.Parameters.AddWithValue("@UserID", UserID);
                                       
                    myCmd.ExecuteNonQuery();
                }
                
                BindProductCart();
                BindCartNumber();
            }
            else if (myQty > PQuantity)
            {
                divQtyError2.Visible = true;
            }
        }
    }
}