Shopping Cart Add To Cart Asp.Net C#

Hi I am really struggling with my code to add paypal sandbox to my page.

So far I have managed to get my Checkout button to direct me to the paypal page where payment occurs.

How ever I have tried to modify my add to cart button to add to the paypal cart without any success what so ever.

Here is my HTML:

 <asp:DataList ID="dlProducts" runat="server" BackColor="White" 
        BorderColor="#CC9966" BorderStyle="None" BorderWidth="1px" CellPadding="4" 
        GridLines="Both" RepeatColumns="3" 
       >
        <ItemTemplate>
            Product Name:
            <asp:Label ID="lblProductNane" runat="server" Text='<%# Bind("ProductName") %>'></asp:Label>
            <br />
            <asp:Image ID="Image1" runat="server" GenerateEmptyAlternateText="True" 
                Height="100px" ImageUrl='<%# "~/ProductImages/"+Eval("ImageName") %>' 
                Width="100px" />
            <br />
            Price:
            <asp:Label ID="lblListPrice" runat="server" 
                Text='<%# Eval("UnitPrice", "{0:C}") %>'></asp:Label>
            <br />
            Qty: 
            <br />
            <asp:LinkButton ID="lnkDetails" runat="server" 
                CommandArgument='<%# Bind("ProductID") %>' onclick="lnkDetails_Click">Click For Details</asp:LinkButton>
             
            <br />
            <form target="paypal" action="https://www.paypal.com/cgi-bin/webscr" method="post">
<input type="hidden" name="cmd" value="_s-xclick">
<asp:HiddenField Value="lblProductName" runat="server" />
<asp:HiddenField Value="lblListPrice" runat="server" />
<asp:ImageButton AlternateText="PayPal — The safer, easier way to pay online." ID="btnBasket" runat="server" CommandArgument='<%# Bind("ProductID") %>' OnClick="btnBasket_Click" ImageUrl="https://www.paypalobjects.com/en_GB/i/btn/btn_cart_LG.gif" />
<img alt="" border="0" src="https://www.paypalobjects.com/en_GB/i/scr/pixel.gif" width="1" height="1" I>
</form>
                        
        </ItemTemplate>
        <SelectedItemStyle BackColor="#FFCC66" Font-Bold="True" ForeColor="#663399" />
    </asp:DataList>

Here is my code behind:

    protected void btnBasket_Click(object sender, System.EventArgs e)
    {
        Response.Write(PaypalPostForm());

        PayPalPostScript(Page);
    }

     public string PaypalPostForm()
     {
        string PostURL = "http://www.paypal.com/cgi-bin/webscr";
        string cmd = "_cart";
        string Upload = "1";
        string BusinessEmail = "";
        string Currency = "GBP";
        string method = "post";
        string shipAmount = "4.95";

        StringBuilder ppForm = new StringBuilder();
        ppForm.AppendFormat("<Form name='frmPP' id='frmPP' action='{0}' method='{1}'>", PostURL, method);
        ppForm.AppendFormat("<input type='hidden' name='shipping' value='{0}'>", shipAmount);
        ppForm.AppendFormat("<input type='hidden' name='cmd' value='{0}'>", cmd);
        ppForm.AppendFormat("<input type='hidden' name='upload' value='{0}'>", Upload);
        ppForm.AppendFormat("<input type='hidden' name='business' value='{0}'>", BusinessEmail);
        ppForm.AppendFormat("<input type='hidden' name='currency_code' value='{0}'>", Currency);
        ppForm.AppendFormat("<input type='hidden' name='item_number_1' value='{0}'>", 1);
        for(int i = 0; i<this.dlProducts.Items.Count; i++)
        {
            Label lbldes = this.dlProducts.Items[i].FindControl("lblProductNane") as Label;
            string Description = (lbldes.Text).ToString();
            Label lblPri = this.dlProducts.Items[i].FindControl("lblListPrice") as Label;
            string Price = (lblPri.Text).ToString();
           ppForm.AppendFormat("&lt;input type='hidden' name='item_name_1' value='{0}'>", Description);
            ppForm.AppendFormat("&lt;input type='hidden' name='amount_1' value='{0}'>", Price);
        }
        ppForm.AppendFormat("&lt;input type='hidden' name='quantity_1' value='{0}'>", 1);
        ppForm.Append("&lt;/form>");
        return ToString();

    }

     private void PayPalPostScript(System.Web.UI.Page Page)
     {
         //This registers Javascript to the page which is used to post the PayPal Form details
         StringBuilder strScript = new StringBuilder();
         strScript.Append("&lt;script language='javascript'>");
         strScript.Append("var ctlForm = document.getElementById('frmPP');");
         strScript.Append("ctlForm.submit();");
         strScript.Append("&lt;/script>");
         ClientScript.RegisterClientScriptBlock(this.GetType(), "PPSubmit", strScript.ToString());
     }

};

Tags: C#, ASP.NET