Safe Casting ToList<T>() in C#

SafeExtensions.cs

    public static class SafeExtensions
    {
        public static IEnumerable<T> SafeToList<T>(this IEnumerable<T> source)
        {
            return source != null ? source.ToList() : null;
        }

        public static T[] SafeToArray<T>(this IEnumerable<T> source)
        {
            return source != null ? source.ToArray() : null;
        }

        // Returns length of array if not null, otherwise zero.
        public static int LengthOrNull<T>(this T[] source)
        {
            return source != null ? source.Length : 0;
        }
    }

Gave LengthOrNull a nicer name.