Vp Asp Shopping Cart 🆒
<% Dim idx, cart, i idx = Request("idx") cart = Session("Cart") For i = idx To UBound(cart) - 1 cart(i) = cart(i + 1) Next ReDim Preserve cart(UBound(cart) - 1)
Sub Session_OnStart Session("Cart") = Array() End Sub : Array(ProductID, ProductName, Price, Quantity) 3. Add to cart ( add_to_cart.asp ) <% Dim pid, pname, price, qty, cart, found, i pid = Request("id") pname = Request("name") price = CDbl(Request("price")) qty = CInt(Request("qty")) If qty < 1 Then qty = 1 vp asp shopping cart
(store in Session("Cart") ):
productID|quantity|price|name^productID2|quantity2|price2|name2^... But a is cleaner. 2. Cart data structure (in Session) On session start ( global.asa ): <% Dim idx, cart, i idx = Request("idx")
' Loop to find if product already in cart For i = 0 To UBound(cart) If cart(i, 0) = pid Then cart(i, 3) = cart(i, 3) + qty found = True Exit For End If Next Example product list ( products
If Not found Then ReDim Preserve cart(UBound(cart) + 1) cart(UBound(cart)) = Array(pid, pname, price, qty) End If
<% ' insert into Orders table ' then insert into OrderItems table Session("Cart") = Array() ' clear cart Response.Redirect("thankyou.asp") %> | Issue | Fix | |--------|------| | Empty cart | Check UBound(Session("Cart")) >= 0 | | Negative quantity | Validate input, set min=0 | | Price tampering | Never trust price from client. Store price in DB, retrieve by ProductID | | Session expiration | Redirect to login or save cart in DB for registered users | | SQL injection | Use parameterized queries (ADODB.Command) | 9. Example product list ( products.asp ) <% Set rs = conn.Execute("SELECT id, name, price FROM products") Do While Not rs.EOF %> <form method="post" action="add_to_cart.asp"> <%=rs("name")%> - <%=FormatCurrency(rs("price"))%> <input type="hidden" name="id" value="<%=rs("id")%>"> <input type="hidden" name="name" value="<%=rs("name")%>"> <input type="hidden" name="price" value="<%=rs("price")%>"> Qty: <input type="number" name="qty" value="1" min="1" size="3"> <input type="submit" value="Add to Cart"> </form> <% rs.MoveNext Loop %> 10. Database schema (minimal) Products table id (auto) | name (text) | price (currency)