电子书删除

删除逻辑

async function removeBook(book) {
  if (book) {
    book.reset()
    if (book.fileName) {
      const removeBookSql = `delete from book where fileName='${book.fileName}'`
      const removeContentsSql = `delete from contents where fileName='${book.fileName}'`
      await db.querySql(removeBookSql)
      await db.querySql(removeContentsSql)
    }
  }
}