///<summary>
/// Get Hash Code.
///</summary>
///<returns>Hash Code for the current instance.</returns>
public override int GetHashCode()
{
int hashCode = base.GetHashCode();
if (_id != null)
{
hashCode += _id.GetHashCode();
}
if (_unit != null)
{
hashCode += _unit.GetHashCode();
}
if (_dimension != null)
{
hashCode += _dimension.GetHashCode();
}
return(hashCode);
}