Calculating Count for IEnumerable (Non Generic)

Question

Can anyone help me with a Count extension method for IEnumerable (non generic interface).

I know it is not supported in LINQ but how to write it manually?

Answer 1

yourEnumerable.Cast<object>().Count() 

To the comment about performance:

I think this is a good example of premature optimization but here you go:

static class EnumerableExtensions {     public static int Count(this IEnumerable source)     {         int res = 0;          foreach (var item in source)             res++;          return res;     } }