Loading class as a list

I have a class

public class Orders
{
    public Orders() {}

    private st开发者_如何转开发ring _idOrder;
    private string _totalPrice;

    public string idOrder 
    { 
        get{ return _idOrder;}
        set { _idOrder = value;}  
    }

    public string totalPrice
    {
        get { return _totalPrice; }
        set { _totalPrice = value; }  
    }
}

I am loading the list from database like this

while (dr.Read())
{
    Orders.idOrder = dr["IdOrder"].ToString();
    Orders.totalPrice= dr["totalPrice"].ToString();
}

It's is showing me only last record. How can I load all the orders and retrieve them back by foreach loop?

Create a list :-)

List<Order> orders = new List<Order>();
while (dr.Read())
{
    Order order = new Order();
    order.idOrder = dr["IdOrder"].ToString();
    order.totalPrice= dr["totalPrice"].ToString();
    orders.Add(order);
}

As you see, I renamed your class from Orders to Order, because that's what it really represents: One order. To have more orders, you need to put those single orders into a list.

It's only showing you the one item, because you're only changing properties on the one item, not instantiating a new one:

var results = new List<Order>();

while (reader.Read())
{
  var order = new Order
  {
    Id = (int)reader["IdOrder"],
    TotalPrice = (decimal)reader["totalPrice"]
  };

  results.Add(order);
}

I think you are looking for something like this:

IEnumberable<Order> FetchOrders()
{
    while(dr.Read())
        yield return new Order {
          idOrder=dr["IdOrder"].ToString(), 
          totalPrice=dr["totalPrice"].ToString()
        });
}

That Orders class represents a single order! If what you need is a list of orders then I suggest you rename that class to Order, and then create a List<Order> (a list of order-objects) and populate that from your query results.

Also (forgive me for being pernickety) "idOrder" is not a good field name. The standard approaches are "orderId" or just plain old "Id" (ID, or even id). Likewise I would expect the price-of-ONE-order to be called just "amount", or even "price"... not "totalPrice"... it'll be too confusing when you come to total-up the totalPrices... get my drift?

Cheers. Keith.

I don't see how that will compile. Orders.idOrder is not a static property, it's an instance property.

If i understand you right you want to use something like this:

List<Order> = new List<Order>();
while (dr.Read())
{
    Order newOrder = new Order();
    newOrder.idOrder = dr["IdOrder"].ToString();
    newOrder.totalPrice= dr["totalPrice"].ToString();
    orderList.Add(newOrder);
}

Notice this that I just discuss more for @Grook Answer. I Think it is so near to what to want.

IEnumberable<Order> FetchOrders()
{
    while(dr.Read())
        yield return new Order {
          idOrder=dr["IdOrder"].ToString(), 
          totalPrice=dr["totalPrice"].ToString()
        });
}

Then You can easily use foreach loop

Foreach(Order order in GetOrders())
{
 doSomething(order);
}

Is it clear?