With VB, trying to create a shopping cart; two ways I think:

adding the items in a database....Not trying this one.

 Adding the articles in session variables, like:

session.add("product_id", price).

then retrieve the data from the database where product_id=product_id..... Ok I think it will work....

the thing is, by the sessoin I can only add two variables (product_id and price ) for each article....

And what if there was another variable, for example size or color.

Can I store 3 variables at a time (product_id, price and color) in a session variable or in something else each time the user adds an item to the cart, and how to?????

In my opinion best way to do this is to create a class that represents a shopping cart item.

So a class that has like a product id, quantity, and other attributes.

So each time a user wants to add an item you would create an instance of this class and add it to session, whether it be directly to session or as a collection of items.

That way you can easily manage the cart items like change its quantity, remove etc 

 I completely agree with Jimmy, it will make maintenance very easy as well as promote a good OO design methodology. I put together an extremely simple example in C#. For the price I only set 2 values and again this is a very very simple example.

 Default.aspx

<form id="form1" runat="server">
    <div>
        <asp:Label ID="Label1" runat="server" Text="My Product Page"></asp:Label>
        <br /><br />
        <asp:ListBox ID="ListBox1" runat="server" AutoPostBack="True">
            <asp:ListItem>Shirts</asp:ListItem>
            <asp:ListItem>Sweaters</asp:ListItem>
            <asp:ListItem>Coats</asp:ListItem>
            <asp:ListItem>Pants</asp:ListItem>
        </asp:ListBox>
        <br />
        <br />
        <asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True">
            <asp:ListItem>Small</asp:ListItem>
            <asp:ListItem>Medium</asp:ListItem>
            <asp:ListItem>Large</asp:ListItem>
            <asp:ListItem>X-Large</asp:ListItem>
            <asp:ListItem>XX-Large</asp:ListItem>
        </asp:DropDownList> <asp:DropDownList ID="DropDownList2" runat="server" AutoPostBack="True">
            <asp:ListItem>Black</asp:ListItem>
            <asp:ListItem>White</asp:ListItem>
            <asp:ListItem>Green</asp:ListItem>
            <asp:ListItem>Blue</asp:ListItem>
            <asp:ListItem>Yellow</asp:ListItem>
            <asp:ListItem>Red</asp:ListItem>
            <asp:ListItem>Orange</asp:ListItem>
            <asp:ListItem>Brown</asp:ListItem>
        </asp:DropDownList>
        <asp:TextBox ID="TextBox1" runat="server" Width="46px"></asp:TextBox><br />
        <br />
        <br />
        <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Order" /><br />
        <br />
        <br />
    </div>
    </form>

Default.aspx.cs

protected void Button1_Click(object sender, EventArgs e)
{
    ShoppingCart cart = new ShoppingCart();
    cart.ProductID = 1;
    cart.ProductName = ListBox1.SelectedItem.Value;
    cart.ProductDescription = "Some Description";
    cart.Quantity = Convert.ToInt32(TextBox1.Text);
    cart.Size = DropDownList1.SelectedItem.Value;
    cart.Color = DropDownList2.SelectedItem.Value;

    if (cart.ProductName == "Sweaters" && cart.Size == "XX-Large")
        cart.Price = 29.95M;
    else
        cart.Price = 19.95M;

    Session["Order"] = cart;

    Response.Redirect("~/OrderDetails.aspx");
}

ShoppingCart.cs 

public class ShoppingCart
{
   private string size;
   public string Size
   {
      get { return size; }
      set { size = value; }
   }
    
   private string color;
   public string Color
   {
      get { return color; }
      set { color = value; }
   }

   private int productID;
   public int ProductID
   {
      get { return productID; }
      set { productID = value; }
   }

   private string productName;
   public string ProductName
   {
      get { return productName; }
      set { productName = value; }
   }

   private string productDescription;
   public string ProductDescription
   {
      get { return productDescription; }
      set { productDescription = value; }
   }

   private int quantity;
   public int Quantity
   {
      get { return quantity; }
      set { quantity = value; }
   }

   private decimal price;
   public decimal Price
   {
      get { return price; }
      set { price = value; }
   }
}
 
OrderDetails.aspx
 
form id="form1" runat="server">
    <div>
        <asp:Label ID="Label1" runat="server" Text="Your Order"></asp:Label>
        <br />
        <br />
        <asp:Label ID="Label" runat="server" Text="ProductID:"></asp:Label>
        <asp:Label ID="ProductIDLabel" runat="server" Text="Label"></asp:Label>
        <br />
        <asp:Label ID="Label2" runat="server" Text="Product Name:"></asp:Label>
        <asp:Label ID="ProductNameLabel" runat="server" Text="Label"></asp:Label>
        <br />
        <asp:Label ID="Label3" runat="server" Text="Description:"></asp:Label>
        <asp:Label ID="ProductDescriptionLabel" runat="server" Text="Label"></asp:Label><br />
        <asp:Label ID="Label4" runat="server" Text="Quantity:"></asp:Label>
        <asp:Label ID="ProductQtyLabel" runat="server" Text="Label"></asp:Label><br />
        <asp:Label ID="Label5" runat="server" Text="Size:"></asp:Label>
        <asp:Label ID="ProductSizeLabel" runat="server" Text="Label"></asp:Label><br />
        <asp:Label ID="Label6" runat="server" Text="Color:"></asp:Label>
        <asp:Label ID="ProductColorLabel" runat="server" Text="Label"></asp:Label><br />
        <asp:Label ID="Label7" runat="server" Text="Price:"></asp:Label>
        <asp:Label ID="ProductPriceLabel" runat="server" Text="Label"></asp:Label></div>
    </form>
 
OrderDetails.aspx.cs 
 
protected void Page_Load(object sender, EventArgs e)
{
    ShoppingCart order = new ShoppingCart();
    order = Session["Order"] as ShoppingCart;

    ProductIDLabel.Text = order.ProductID.ToString();
    ProductNameLabel.Text = order.ProductName;
    ProductDescriptionLabel.Text = order.ProductDescription;
    ProductQtyLabel.Text = order.Quantity.ToString();
    ProductSizeLabel.Text = order.Size;
    ProductColorLabel.Text = order.Color;
    ProductPriceLabel.Text = order.Price.ToString();
}
 
 
 

What you need to do is cast the Session object to a Shopping Cart object. I could have also written that line as such:

order = (ShoppingCart)Session["Order"]; 

333bob:

order = Session["Order"] as ShoppingCart;

The VB equivalent w ould be

order = CType(Session("Order"), ShoppingCart) 

Hi

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