Hi i am new to asp.net and have followed a tutorial in creating a shopping cart and thats working fine. I would like to modify it to produce the products from my database rather than get static products from a class which it does now.
Sorry for the masses of code but just thought i would put it in so you can understand.
If anyone could help that would be great.
Many Thanks in advance
Heres my code
The page which displays the products:
<div class="contentBox">
<h1 class="heading">Place and Rrder</h1>
<div>Shoes - <asp:LinkButton runat="server" ID="btnAddShirt" OnClick="btnAddShoes_Click">Add To Cart</asp:LinkButton></div>
<div>Shirt - <asp:LinkButton runat="server" ID="btnAddShorts" OnClick="btnAddShirt_Click">Add To Cart</asp:LinkButton></div>
<div>Pants - <asp:LinkButton runat="server" ID="btnAddShoes" OnClick="btnAddPants_Click">Add To Cart</asp:LinkButton></div>
<a href="ViewCart.aspx">View Cart</a>
</div>
and the code behind:
protected void btnAddShoes_Click(object sender, EventArgs e) {
// Add product 1 to the shopping cart
ShoppingCart.Instance.AddItem(1);
// Redirect the user to view their shopping cart
Response.Redirect("ViewCart.aspx");
}
protected void btnAddShirt_Click(object sender, EventArgs e) {
ShoppingCart.Instance.AddItem(2);
Response.Redirect("ViewCart.aspx");
}
protected void btnAddPants_Click(object sender, EventArgs e) {
ShoppingCart.Instance.AddItem(3);
Response.Redirect("ViewCart.aspx");
}
}The view cart page:
<asp:GridView runat="server" ID="gvShoppingCart" AutoGenerateColumns="false" EmptyDataText="There is nothing in your shopping cart." GridLines="None" Width="100%" CellPadding="5" ShowFooter="true" DataKeyNames="ProductId" OnRowDataBound="gvShoppingCart_RowDataBound" OnRowCommand="gvShoppingCart_RowCommand">
<HeaderStyle HorizontalAlign="Left" BackColor="#3D7169" ForeColor="#FFFFFF" />
<FooterStyle HorizontalAlign="Right" BackColor="#6C6B66" ForeColor="#FFFFFF" />
<AlternatingRowStyle BackColor="#F8F8F8" />
<Columns>
<asp:BoundField DataField="Description" HeaderText="Description" />
<asp:TemplateField HeaderText="Quantity">
<ItemTemplate>
<asp:TextBox runat="server" ID="txtQuantity" Columns="5" Text='<%# Eval("Quantity") %>'></asp:TextBox><br />
<asp:LinkButton runat="server" ID="btnRemove" Text="Remove" CommandName="Remove" CommandArgument='<%# Eval("ProductId") %>' style="font-size:12px;"></asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="UnitPrice" HeaderText="Price" ItemStyle-HorizontalAlign="Right" HeaderStyle-HorizontalAlign="Right" DataFormatString="{0:C}" />
<asp:BoundField DataField="TotalPrice" HeaderText="Total" ItemStyle-HorizontalAlign="Right" HeaderStyle-HorizontalAlign="Right" DataFormatString="{0:C}" />
</Columns>
</asp:GridView>
<br />
<asp:Button runat="server" ID="btnUpdateCart" Text="Update Cart" OnClick="btnUpdateCart_Click" />
and the code behind
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
BindData();
}
protected void BindData() {
gvShoppingCart.DataSource = ShoppingCart.Instance.Items;
gvShoppingCart.DataBind();
}
protected void gvShoppingCart_RowDataBound(object sender, GridViewRowEventArgs e) {
if (e.Row.RowType == DataControlRowType.Footer) {
e.Row.Cells[3].Text = "Total: " + ShoppingCart.Instance.GetSubTotal().ToString("C");
}
}
/**
* This is the method that responds to the Remove button's click event
*/
protected void gvShoppingCart_RowCommand(object sender, GridViewCommandEventArgs e) {
if (e.CommandName == "Remove") {
int productId = Convert.ToInt32(e.CommandArgument);
ShoppingCart.Instance.RemoveItem(productId);
}
// We now have to re-setup the data so that the GridView doesn't keep
// displaying the old data
BindData();
}
protected void btnUpdateCart_Click(object sender, EventArgs e) {
foreach (GridViewRow row in gvShoppingCart.Rows) {
if (row.RowType == DataControlRowType.DataRow) {
try {
// Get the productId from the GridView's datakeys
int productId = Convert.ToInt32(gvShoppingCart.DataKeys[row.RowIndex].Value);
// Find the quantity TextBox and retrieve the value
int quantity = int.Parse(((TextBox)row.Cells[1].FindControl("txtQuantity")).Text);
ShoppingCart.Instance.SetItemQuantity(productId, quantity);
} catch (FormatException) { }
}
}
BindData();
}The shopping cart Class:
public class ShoppingCart {
#region Properties
public List<CartItem> Items { get; private set; }
#endregion
#region Singleton Implementation
// Readonly properties can only be set in initialization or in a constructor
public static readonly ShoppingCart Instance;
// The static constructor is called as soon as the class is loaded into memory
static ShoppingCart() {
// If the cart is not in the session, create one and put it there
// Otherwise, get it from the session
if (HttpContext.Current.Session["ASPNETShoppingCart"] == null) {
Instance = new ShoppingCart();
Instance.Items = new List<CartItem>();
HttpContext.Current.Session["ASPNETShoppingCart"] = Instance;
} else {
Instance = (ShoppingCart)HttpContext.Current.Session["ASPNETShoppingCart"];
}
}
// A protected constructor ensures that an object can't be created from outside
protected ShoppingCart() { }
#endregion
#region Item Modification Methods
/**
* AddItem() - Adds an item to the shopping
*/
public void AddItem(int productId) {
// Create a new item to add to the cart
CartItem newItem = new CartItem(productId);
// If this item already exists in our list of items, increase the quantity
// Otherwise, add the new item to the list
if (Items.Contains(newItem)) {
foreach (CartItem item in Items) {
if (item.Equals(newItem)) {
item.Quantity++;
return;
}
}
} else {
newItem.Quantity = 1;
Items.Add(newItem);
}
}
/**
* SetItemQuantity() - Changes the quantity of an item in the cart
*/
public void SetItemQuantity(int productId, int quantity) {
// If we are setting the quantity to 0, remove the item entirely
if (quantity == 0) {
RemoveItem(productId);
return;
}
// Find the item and update the quantity
CartItem updatedItem = new CartItem(productId);
foreach (CartItem item in Items) {
if (item.Equals(updatedItem)) {
item.Quantity = quantity;
return;
}
}
}
/**
* RemoveItem() - Removes an item from the shopping cart
*/
public void RemoveItem(int productId) {
CartItem removedItem = new CartItem(productId);
Items.Remove(removedItem);
}
#endregion
#region Reporting Methods
/**
* GetSubTotal() - returns the total price of all of the items
* before tax, shipping, etc.
*/
public decimal GetSubTotal() {
decimal subTotal = 0;
foreach (CartItem item in Items)
subTotal += item.TotalPrice;
return subTotal;
}
#endregion
}the products class:
public class Product
{
public int Id { get; set; }
public decimal Price { get; set; }
public string Description { get; set; }
public Product(int id)
{
this.Id = id;
switch (id) {
case 1:
this.Price = 19.95m;
this.Description = "Shoes";
break;
case 2:
this.Price = 9.95m;
this.Description = "Shirt";
break;
case 3:
this.Price = 14.95m;
this.Description = "Pants";
break;
}
}
}and the Cart Items class:
public class CartItem : IEquatable<CartItem> {
#region Properties
// A place to store the quantity in the cart
public int Quantity { get; set; }
private int _productId;
public int ProductId {
get { return _productId; }
set {
// To ensure that the Prod object will be re-created
_product = null;
_productId = value;
}
}
private Product _product = null;
public Product Prod {
get {
// Lazy initialization - the object won't be created until it is needed
if (_product == null) {
_product = new Product(ProductId);
}
return _product;
}
}
public string Description {
get { return Prod.Description; }
}
public decimal UnitPrice {
get { return Prod.Price; }
}
public decimal TotalPrice {
get { return UnitPrice * Quantity; }
}
#endregion
// CartItem constructor just needs a productId
public CartItem(int productId) {
this.ProductId = productId;
}
public bool Equals(CartItem item) {
return item.ProductId == this.ProductId;
}
}