helper class to clear the value of a table field

static boolean clearValueOfField(
    Common _record,
    FieldID _fieldID)
{
    DictField dictField;
    ;

    dictField = new DictField(_record.TableId, _fieldID);
    if (!dictField)
        return false;

    switch (dictField.baseType())
    {
        case Types::String :
        case Types::VarString :
            _record.(_fieldID) = "";
            return true;

        case Types::Date :
            _record.(_fieldID) = datenull();
            return true;

        case Types::Real :
        case Types::Integer :
        case Types::Enum :
            _record.(_fieldID) = 0;
            return true;

        default :
            return false;
    }

    return false;
}