I have a number of controls that inherit from a generic base class and this class implements an interface IMyInterface.
So far I tried:
var results = from c in this.Controls.Cast<Control>()
where c.GetType().GetInterfaces().Contains(typeof(IMyInterface))
select c as IMyInterface;
However, the above doesn't return any results even though it should.
How can I use Linq to get a list of controls on a form that implement this interface?
If I understood you correctly, you could basically use:
var results = this.Controls.OfType<BaseGeneric>().ToList();
OfType<IMyInterface>.Given the following extension method:
public static class TypeExtensions
{
public static IEnumerable<Type> BaseTypesAndSelf(this Type type)
{
while (type != null)
{
yield return type;
type = type.BaseType;
}
}
}
You want something like:
var result = from c in this.Controls.Cast<Control>()
where c.GetType().BaseTypesAndSelf().Any(t => t.IsGenericType && t.GetGenericTypeDefinition() == typeof(BaseGeneric<>))
select c;
You might want to have your BaseGeneric<T> inherit from some even more abstract BaseGenericBase, or implement some non-generic IBaseGeneric interface, to make this sort of thing simpler.
class Program
{
static void Main(string[] args)
{
A test1 = new A();
B test2 = new B();
C test3 = new C();
List<object> test4 = new List<object>() { test1, test2, test3 };
List<object> test5 = test4.FindAll(x => x is A).ToList();
}
}
public class A
{
public A() { }
}
public class B
{
public B() {}
}
public class C : A
{
public C()
:base()
{
}
}
