ASP.NET MVC Html Helper for generating a select list from a dictionary

ToSelectList.cs

public static List<SelectListItem> ToSelectList(this Dictionary<string, string> items, string defaultItem, bool insertBlankItem = false)
{
	string[] defaultItems = new[] { defaultItem };
	if (!string.IsNullOrWhiteSpace(defaultItem))
	{
		defaultItems = defaultItem.Split(',');
	}

	var i = items.Select(pair => new SelectListItem
	{
		Text = pair.Value,
		Value = pair.Key,
		Selected = defaultItems.Contains(pair.Key)
	}).ToList();

	if (insertBlankItem)
	{
		i.Insert(0, new SelectListItem());
	}

	return i;
}