RangeField

gistfile1.cs

public class RangeField<T>
	{
		private T Start { get; set; }
		private T End { get; set; }

		public RangeField()
		{
			Start = default(T);
			End = default(T);
		}

		public static RangeField<T> New(T val)
		{
			return new RangeField<T> { Start = val, End = val };
		}

		public static RangeField<T> New(T start, T end)
		{
			return new RangeField<T> { Start = start, End = end };
		}

		public bool HasRange()
		{
			return HasStart() && HasEnd();
		}

		public bool HasStart()
		{
			return (!IsNullOrDefault(Start));
		}

		public bool HasEnd()
		{
			return (!IsNullOrDefault(End));
		}

		private static bool IsNullOrDefault<T>(T argument)
		{
			// deal with normal scenarios
			if (argument == null)
				return true;

			if (object.Equals(argument, default(T)))
				return true;

			// deal with non-null nullables
			Type methodType = typeof(T);
			if (Nullable.GetUnderlyingType(methodType) != null)
				return false;

			// deal with boxed value types
			Type argumentType = argument.GetType();
			if (argumentType.IsValueType && argumentType != methodType)
			{
				object obj = Activator.CreateInstance(argument.GetType());
				return obj.Equals(argument);
			}

			return false;
		}
	}