asp. net Implementation of Shopping Cart Based on HashTable

In this paper, an example of asp. net based on HashTable to achieve shopping cart method. Share it for your reference, as follows:

// When a user buys a product, 
if (e.CommandName.ToLower() == "buy") 
{
 // Judge whether the shopping cart of the user is empty or not   If empty, assign 1 A 
 Hashtable table;
 if (Session["car"] == null)
 {
  table = new Hashtable();
 }
 else
 {
  // User shopping cart already exists   The data is fetched 
  table = Session["car"] as Hashtable;
 }
 // If the item information is not included in the user's shopping cart   Add the 1 New merchandise 
 if (!table.Contains(e.CommandArgument))
 {
  table.Add(e.CommandArgument, 1);// Add 1 New merchandise   Quantity is 1
 }
 else 
 {
  // If the item information already exists in the shopping cart   Add the quantity of the item 1  According to HashTable Gets the corresponding value with the key of 
  int count = Convert.ToInt32(table[e.CommandArgument].ToString());
  // Add the quantity of the commodity 1
  table[e.CommandArgument] = (count + 1);
 }
 // Save commodity information 
 Session["car"] = table;
 Response.Redirect("shoppingcar.aspx");
}
// Commodity information list 
private void shoplist()
{
  Hashtable table;
  if (Session["car"] == null)
  {
   table = new Hashtable();
  }
  else
  {
   table = Session["car"] as Hashtable;
  }
  if (table.Count == 0)
  {
   Image13.Visible = true;
   Msg.Visible = true;
   Msg.Text = "<b style="color:red" mce_style="color:red"> You haven't been shopping yet? Go shopping quickly !</b>";
  }
  string[] Arrkey = new string[table.Count];
  int[] ArrVal = new int[table.Count];
  table.Keys.CopyTo(Arrkey, 0);
  table.Values.CopyTo(ArrVal, 0);
  // Definition string   Form  ('1,2,3')
  string Products = "('";
  int k = 0;
  for (int j = 0; j < Arrkey.Length; j++)
  {
   if(k>0)Products += "','"; k++;
   Products += Arrkey.GetValue(j).ToString();
  }
  Products += "')";
  DataSet ds = productbll.GetInfoByWhere(" pid in " + Products);
  DataTable Table1 = new DataTable();
  Table1 = ds.Tables[0];
  Table1.Columns.Add(new DataColumn("shuliang", System.Type.GetType("System.Int32")));
  // Get pid Value of   And set it to Table1 Primary key of 
  DataColumn[] keys = { Table1.Columns["pid"]};
  Table1.PrimaryKey = keys;
  foreach (string key in table.Keys)
  {
   Table1.Rows.Find(key)["shuliang"] = table[key];// Get the value according to the key   Quantity of goods 
  }
  Table1.Columns.Add(new DataColumn("zongjia", System.Type.GetType("System.Double"), "hotprice*shuliang"));
  for (int n = 0; n < Table1.Rows.Count; n++) 
  {
   tPrice +=Convert.ToDouble(Table1.Rows[n]["zongjia"]);
  }
  Label1.Text = tPrice.ToString();
  Session["total"] = Label1.Text.ToString();
  MyGrid.DataSource = Table1.DefaultView;
  MyGrid.DataBind();
}
#region  Delete from shopping cart 1 Article commodity information 
protected void MyGrid_RowCommand(object sender, GridViewCommandEventArgs e)
{
  Hashtable table;
  if (Session["car"] == null)
  {
   table = new Hashtable();
  }
  else
  {
   table = Session["car"] as Hashtable;
  }
  // If you click the Delete button   The item information is removed from the shopping cart 
  if (e.CommandName.ToLower() == "delete")
  {
   if (table.ContainsKey(e.CommandArgument))
   {
    // From HashTable Remove the information of this item from the ( Commodity number )  Key : Be the commodity number   Value is : Quantity of goods 
    table.Remove(e.CommandArgument);
   }
   Msg.Text = (string)e.CommandArgument;
  }
  Session["car"] = table;
  // Invoke method 
  shoplist();
}
#endregion

I hope this article is helpful to everyone's asp. net programming.