c# - A list of multiple data types?

Question

I have two classes as such:

public class MachineLine
{
    public double X1;
    public double Y1;
    public double X2;
    public double Y2;
    public double Thickness;
}

public class MachineCircle
{
    public double CenterX;
    public double CenterY;
    public double Radius;
}

I want to make a List which can hold both of these, but I don't want my list to be able to hold any other data type. How can this be done?

Answer 1

The easiest way to do this is to declare an interface, and have both types implement it:

public interface IMachine { … }

public class MachineLine : IMachine
{
    public double X1;
    public double Y1;
    public double X2;
    public double Y2;
    public double Thickness;
}

public class MachineCircle : IMachine
{
    public double CenterX;
    public double CenterY;
    public double Radius;
}

Then you can do this:

List<IMachine> m = new List<IMachine>();