asp.Net HashTableによるカートの実現方法

本文の例はaspを述べた.NetはHashTableに基づいてカートを実現する方法です.皆さんの参考にしてください.具体的には以下の通りです.

//       
if (e.CommandName.ToLower() == "buy") 
{
 //                     
 Hashtable table;
 if (Session["car"] == null)
 {
  table = new Hashtable();
 }
 else
 {
  //              
  table = Session["car"] as Hashtable;
 }
 //                         
 if (!table.Contains(e.CommandArgument))
 {
  table.Add(e.CommandArgument, 1);//           1
 }
 else 
 {
  //                       1   HashTable         
  int count = Convert.ToInt32(table[e.CommandArgument].ToString());
  //        1
  table[e.CommandArgument] = (count + 1);
 }
 //      
 Session["car"] = table;
 Response.Redirect("shoppingcar.aspx");
}
//      
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 = "       ？     !";
  }
  string[] Arrkey = new string[table.Count];
  int[] ArrVal = new int[table.Count];
  table.Keys.CopyTo(Arrkey, 0);
  table.Values.CopyTo(ArrVal, 0);
  //         ('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")));
  //  pid         Table1   
  DataColumn[] keys = { Table1.Columns["pid"]};
  Table1.PrimaryKey = keys;
  foreach (string key in table.Keys)
  {
   Table1.Rows.Find(key)["shuliang"] = table[key];//            
  }
  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              
protected void MyGrid_RowCommand(object sender, GridViewCommandEventArgs e)
{
  Hashtable table;
  if (Session["car"] == null)
  {
   table = new Hashtable();
  }
  else
  {
   table = Session["car"] as Hashtable;
  }
  //                      
  if (e.CommandName.ToLower() == "delete")
  {
   if (table.ContainsKey(e.CommandArgument))
   {
    // HashTable         (    )  :        :    
    table.Remove(e.CommandArgument);
   }
   Msg.Text = (string)e.CommandArgument;
  }
  Session["car"] = table;
  //    
  shoplist();
}
#endregion

本文で述べたように皆さんにasp.Netプログラミングが役立ちます.