add columns with textboxes in gridview using C#

Question

I'm working on a shopping cart in a website and I have my items(which have been added to the cart) in an arraylist. And using these values I've read the rest of the values from the db and and have populated on the gridview successfully.

        if (d1.Read())
        {
            d1.Close();
            sda.SelectCommand = searchResult;
            sda.Fill(dt);
            GridView2.DataSource = dt;
            GridView2.DataBind();
        }

How can I add an additional column named "Quantity" in this gridview along with a text box so that user can enter a value for the qunatity for each item displayed in the gridview?

Any help/suggestions/links would be greatly appreciated.

thanks,

//edit 2

<asp:GridView ID="GridView2" runat="server" BackColor="#388AD0"
    BorderColor="Black" BorderStyle="Solid" BorderWidth="1px" CellPadding="3" ForeColor="Black"
    GridLines="Vertical" Height="160px" Style="left: 72px;
    position: relative; top: 8px" Width="504px" AllowPaging="True" PageSize="5">
    <FooterStyle BackColor="#E0E0E0" />
    <PagerStyle BackColor="Silver" ForeColor="Black" HorizontalAlign="Center" />
    <SelectedRowStyle BackColor="#388AD0" Font-Bold="True" ForeColor="White" />
    <HeaderStyle BackColor="Black" Font-Bold="True" ForeColor="White" />
    <AlternatingRowStyle BackColor="#388AD0" />
    <PagerSettings Mode="NextPrevious" />
</asp:GridView>

//edit 3

public void additem(string additem) 
{
    DataTable dt = new DataTable();
    string ConnectionString = @"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\ewap_k.mdf;Integrated Security=True;User Instance=True";
    using (SqlConnection searchCon = new SqlConnection(ConnectionString))
    {
        using (SqlCommand searchResult = new SqlCommand("SELECT ItemID, Name, RelDate, Price, Status FROM item_k WHERE ItemID IN ( " + itemIDs + ")", searchCon))
        {
            searchCon.Open();
            SqlDataReader d1 = searchResult.ExecuteReader();
            SqlDataAdapter sda = new SqlDataAdapter();

            if (d1.Read())
            {
                d1.Close();
                sda.SelectCommand = searchResult;
                sda.Fill(dt);
                GridView1.DataSource = dt;
                GridView1.DataBind();
            }
            else { }
            searchCon.Close();
        }
    }
}

//edit 4

<asp:GridView ID="GridView1" runat="server" Style="left: 8px; position: relative;
    top: 0px">
    <Columns>
        <asp:BoundField DataField="ItemID"  Visible="false"/>
        <asp:BoundField DataField="Name" />
        <asp:BoundField DataField="RelDate" />
        <asp:TemplateField>
        <ItemTemplate>
            <asp:TextBox ID="TextBox1" runat="server" Text=""></asp:TextBox>
        </ItemTemplate>
    </asp:TemplateField>
        <asp:BoundField DataField="Price" />
        <asp:BoundField DataField="Status" />
    </Columns>
</asp:GridView>

Answer 1

You can add a template field and drop the textbox in the ItemTemplate as such:

<asp:TemplateField>
            <ItemTemplate>
                <asp:TextBox ID="TextBox1" runat="server" Text=""></asp:TextBox>
            </ItemTemplate>
        </asp:TemplateField>

[Edit] Here's a more complete grid:

<asp:GridView ID="GridView1" runat="server">
    <Columns>
        <asp:BoundField />
        <asp:BoundField />
        <asp:TemplateField>
            <ItemTemplate>
                <asp:TextBox ID="TextBox1" runat="server" Text=""></asp:TextBox>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>

Notice that the TemplateField shows up wherever I decide to put it in the list of columns. If that still isn't working for you, can you post your GridView markup so I can see what you've got?

[Edit 2] Here's an updated version of your grid. You'll just need to set up the BoundFields to bind to whichever value in your dataset that you need.

<asp:GridView ID="GridView2" runat="server" BackColor="#388AD0" BorderColor="Black"
    BorderStyle="Solid" BorderWidth="1px" CellPadding="3" ForeColor="Black" GridLines="Vertical"
    Height="160px" Style="left: 72px; position: relative; top: 8px" Width="504px"
    AllowPaging="True" PageSize="5">
    <Columns>
        <asp:BoundField />
        <asp:BoundField />
        <asp:TemplateField>
            <ItemTemplate>
                <asp:TextBox ID="TextBox1" runat="server" Text=""></asp:TextBox>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
    <FooterStyle BackColor="#E0E0E0" />
    <PagerStyle BackColor="Silver" ForeColor="Black" HorizontalAlign="Center" />
    <SelectedRowStyle BackColor="#388AD0" Font-Bold="True" ForeColor="White" />
    <HeaderStyle BackColor="Black" Font-Bold="True" ForeColor="White" />
    <AlternatingRowStyle BackColor="#388AD0" />
    <PagerSettings Mode="NextPrevious" />
</asp:GridView>