/// <summary>
/// Checks whether the specified key is represented in the index.
/// </summary>
public bool IndexKeyExists(object indexKey)
{
return(ItemGroups.ContainsKey(CastIndexKey(indexKey)));
}
/// <summary>
/// Checks whether the specified key is represented in the index.
/// </summary>
public bool IndexKeyExists(int indexKey)
{
return(ItemGroups.ContainsKey(indexKey));
}