Insert rows into database from gridview

Question

i am trying to insert records from gridview to database by using below code,but record is not getting insert,please have a look.

protected void Button1_Click(object sender, EventArgs e)
        {
            foreach (GridViewRow row in this.GridView1.Rows)
            {
                if (row.RowType == DataControlRowType.DataRow)
                {
                    // SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["con"].ConnectionString);
                    SqlCommand cmd = new SqlCommand("INSERT INTO tbl_Books VALUES(@B_Name,@B_IBN,@QTY)", con);
                    cmd.Parameters.AddWithValue("@B_Name", row.Cells[0].Text);
                    cmd.Parameters.AddWithValue("@B_IBN", row.Cells[1].Text);
                    cmd.Parameters.AddWithValue("@QTY", row.Cells[2].Text);
                    con.Open();
                    cmd.ExecuteScalar();
                    con.Close();
                }
            }
        }