I'm doing a heavy bit of reflection in my current project, and I'm trying to provide a few helper methods just to keep everything tidy.
I'd like to provide a pair of methods to determine if a type or instance implements IEnumerable
– regardless of the type T
. Here is what I have at the moment:
public static bool IsEnumerable(this Type type)
{
return (type is IEnumerable);
}
public static bool IsEnumerable(this object obj)
{
return (obj as IEnumerable != null);
}
When I test them using
Debug.WriteLine("Type IEnumerable: " + typeof(IEnumerable).IsEnumerable());
Debug.WriteLine("Type IEnumerable<>: " + typeof(IEnumerable<string>).IsEnumerable());
Debug.WriteLine("Type List: " + typeof(List<string>).IsEnumerable());
Debug.WriteLine("Type string: " + typeof(string).IsEnumerable());
Debug.WriteLine("Type DateTime: " + typeof(DateTime).IsEnumerable());
Debug.WriteLine("Instance List: " + new List<string>().IsEnumerable());
Debug.WriteLine("Instance string: " + "".IsEnumerable());
Debug.WriteLine("Instance DateTime: " + new DateTime().IsEnumerable());
I get this as the result:
Type IEnumerable: False
Type IEnumerable<>: False
Type List: False
Type string: False
Type DateTime: False
Instance List: True
Instance string: True
Instance DateTime: False
The type method doesn't appear to work at all – I had expected a true
for the direct System.Collections.IEnumerable
match at least.
I'm aware that string
is technically enumerable, albeit with a few caveats. Ideally in this case, however, I'd need the helper method to return false
for it. I just need the instances with a defined IEnumerable<T>
type to return true
.
I've probably just missed something fairly obvious – can anyone point me in the right direction?
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