How to add one column in Gridview

Question

How to Add dynamically One column in Gridview for Barcode

 

<div id="gridContainer" style="overflow: scroll">
             <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False"
                 CssClass="myGrid" AlternatingRowStyle-CssClass="alt" CellPadding="3"
                 AllowPaging="True" BackColor="White" BorderColor="#CCCCCC" BorderStyle="None"
                 BorderWidth="1px" DataSourceID="dsProduct" Width="1019px"
                  Font-Names="Arial" onrowdatabound="GridView1_RowDataBound">
              <AlternatingRowStyle CssClass="alt"></AlternatingRowStyle>
                 <Columns>
                     <asp:BoundField DataField="id" HeaderText="Id" InsertVisible="False"
                         ReadOnly="True" SortExpression="id" />
                     <asp:BoundField DataField="pname" HeaderText="Name"
                         SortExpression="pname" />
                     <asp:BoundField DataField="subhead" HeaderText="Code"
                         SortExpression="subhead" />
                     <asp:BoundField DataField="hsn" HeaderText="HSN" SortExpression="hsn" />
                     <asp:BoundField DataField="qty" HeaderText="Quantity" SortExpression="qty" />
                     <asp:BoundField DataField="cprice" HeaderText="Price" SortExpression="cprice" />
                     <asp:BoundField DataField="tax" HeaderText="Tax %" SortExpression="tax" />
                     <asp:HyperLinkField HeaderText="Action" Text="Edit / Delete" />
                 </Columns>
                 <FooterStyle BackColor="White" ForeColor="Black" />
                 <HeaderStyle BackColor="#006699" Font-Bold="True" ForeColor="White" HorizontalAlign="Center" />
                 <PagerStyle BackColor="White" ForeColor="#000066" HorizontalAlign="Right" />
                 <RowStyle ForeColor="#000066" />
                 <SelectedRowStyle BackColor="#669999" Font-Bold="True" ForeColor="White" />
                 <SortedAscendingCellStyle BackColor="#F1F1F1" />
                 <SortedAscendingHeaderStyle BackColor="#007DBB" />
                 <SortedDescendingCellStyle BackColor="#CAC9C9" />
                 <SortedDescendingHeaderStyle BackColor="#00547E" />
                </asp:GridView>


                        <asp:SqlDataSource ID="dsProduct" runat="server"
                  ConnectionString="<%$ ConnectionStrings:dbcon1 %>"
                  SelectCommand="SELECT [id], [pname], [subhead], [qty], [cprice], [hsn], [tax] FROM [offset]">
              </asp:SqlDataSource>


                        <asp:Button ID="btnreport" runat="server" Text="Report" CssClass="btn-primary mar"
                            width="105px" />
         </div>

 How to add new column Dynamically for Bardcode in after Tax column ; Barcode Generated by code