Several classes inherit from abstract class Illness and overrides a field name
Illness.cs:
namespace health;
abstract class Illness{
public abstract string name { get;}
}
class Cancer : Illness{
public override string name {
get{ return "Cancer";}
}
}
class Covid : Illness{
public override string name {
get{ return "Covid";}
}
}
There is an empty list List<Illness> illnesses = new List<Illness> in main class and the goal is to make a method, which adds a value to illnesses list only if this list doesn't contain the given class already.
Tried to do this:
public void addIllness(Illness illness){
if (!illnesses.Contains(illness)){
illnesses.Add(illness);
}
}
but not working.
You can (as mentioned by Lei Yang) solve this by checking he type:
if(!illnesses.Any(i=>i is typeof(Covid)){ ... } for a specific type.if (!illnesses.Any(i => i.GetType() == illness.GetType())) { ... } comparing the type of the objects.You could also create a generic method to achieve this in a nice manner:
public void Add<T>(T illness) where T : Illness{
if(!illnesses.Any(t=>t is T)){
illnesses.Add(illness);
}
}
As you are overriding name you could even use that for better performance:
if(!illnesses.Any(i=>i.name == illness.name)){ ... }
This is however more or less the explicit version of what (again) @Lei Yang proposed in implementing IEquatable.
This however seems to be a bit strange of an approach, you should use objects when you can have more than one instance of a class, else maybe reconsider adding a "IllnessType" enum beside the Name and ditch the inheritance.
You can check class using GetType method.
if (!illnesses.Any(i => i.GetType() == illness.GetType()))
{
illnesses.Add(illness);
}