For a homework assignment i need to create a List<T>
, add objects to it, and display the objects toString. Here is what i have:
public class Order
{
...
public List<OrderLine> orderLines;
public Order(User user1)
{
...
orderLines = new List<OrderLine>();
}
public void AddOrderLine(OrderLine newOrderLine)
{
orderLines.Add(newOrderLine);
}
}
public class OrderLine
{
public OrderLine(Product p1, int q1)
{
...
}
public override string ToString() //Required by teacher
{
string myOrderLine;
myOrderLine = String.Format("[Product name: {0}; Price: {1}; Quantity: {2}]",
product.name, product.price, quantity);
return myOrderLi开发者_开发技巧ne;
}
}
When adding oerderLines.Add(newOrderLine) new OrderLine is an object created in another class that has a working toString. How do i display all the newOrderLines from the Program.CS?
I assume your main method looks something like this:
{
User user = new User();
Order order = new Order(user);
OrderLine orderLine1 = new OrderLine();
order.AddOrderLine(orderLine1);
}
If I understand what you say correctly, OrderLine already overrides ToString(), so that when you call ToString(), it returns something "human-meaningful". In that case, the only thing you need to do is something along the lines of
foreach (var orderLine in order.orderLines)
{
Console.WriteLine(orderLine.ToString());
}
Note that it is considered good practice not to publicly expose a field, like orderLines. Better make it private, and create a public property like:
public IEnumerable<OrderLine> OrderLines
{
get { return this.orderLines; }
}
Assuming you have the working .ToString()
for the OrderLine class. If you just want to display them to the console, you can do a simple:
foreach(OrderLine orderline in orderLines)
System.Console.WriteLine(orderline.ToString());
edit:
Two simple ways to do this is either the way Mathias outlined quite nicely or put my code inside your Order
class. For example, add a new method like this:
public void PrintOrders()
{
foreach(OrderLine orderline in this.orderLines)
System.Console.WriteLine(orderline.ToString());
}
You would use it like:
User user = new User();
Order order = new Order(user);
OrderLine orderLine = new OrderLine();
order.AddOrderLine(orderLine);
order.PrintOrders();
Please note that it is generally not considered good practice to have classes printing to the console. I just wanted to show you a different way of approaching the problem.
if you have something like this in your Program.cs to populate your Order object
var order = new Order();
order.AddOrderLine(...);
//this is how you can display each item ToString in the collection
foreach(var o in order.orderLines)
{
Console.WriteLine(o.ToString());
}
just check for any typo or syntax error as I only typed this here inline
Is this what you need?
public static void Main(string[] args)
{
Order order = new Order();
OrderLine line1 = new OrderLine(...);
OrderLine line2 = new OrderLine(...);
OrderLine line3 = new OrderLine(...);
order.AddOrderLine(line1);
order.AddOrderLine(line2);
order.AddOrderLine(line3);
foreach (OrderLine line in order.orderLines)
{
Console.WriteLine(line.ToString());
}
}
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