public override string ToString(FormatType format, object supplement = null) { switch (format) { case FormatType.Brief: return($"{Id}.{Word} [{Abbreviation}]"); case FormatType.Detail: return($"{Id}.{Word} [{Abbreviation}]{Pinyin?.BeIfNotWhiteSpace($"\n拼音:{Pinyin}")}{Explanation?.BeIfNotWhiteSpace($"\n解释:{Explanation}")}{Derivation?.BeIfNotWhiteSpace($"\n来源:{Derivation}")}{Example?.BeIfNotWhiteSpace($"\n例子:{Example}")}"); } return(null); }