Exemplo n.º 1
1
 // Parses a single book.
 Book ParseBook(XmlReader reader)
 {
     var book = new Book();
     while (reader.Read())
         if (reader.NodeType == XmlNodeType.Element) {
             string parseType;
             switch (reader.LocalName) {
             case "etext":
                 book.Number = int.Parse(reader.GetAttribute("ID", RDF).Substring(5),
                                             CultureInfo.InvariantCulture);
                 break;
             case "title":
                 parseType = reader.GetAttribute("parseType", RDF);
                 if (parseType != "Literal")
                     throw new ApplicationException("Unrecognized parse type.");
                 book.Title = reader.ReadElementContentAsString();
                 break;
             case "description":
                 book.Notes = ParseText(reader);
                 break;
             case "creator":
                 book.Authors = ParsePersonsAndEra(book, reader);
                 break;
             case "contributor":
                 // Eras of contributors do not affect the era of the book intentionally.
                 // Contributors might be not only illustrators, who would live at the
                 // same time as authors, but also people who retyped the book and
                 // uploaded it to the Project Gutenberg web site. They would mess the
                 // era of the book which is supposed to embrace the time when the actual
                 // paper book was written.
                 book.Contributors = ParsePersons(reader);
                 break;
             case "language":
                 if (!reader.ReadToDescendant("value", RDF))
                     throw new ApplicationException("Missing language value.");
                 book.Language = reader.ReadElementContentAsString();
                 break;
             case "subject":
                 using (var subreader = reader.ReadSubtree())
                     book.Tags = ParseTags(subreader).ToArray();
                 break;
             case "created":
                 if (!reader.ReadToDescendant("value", RDF))
                     throw new ApplicationException("Missing creation date value.");
                 book.Included = reader.ReadElementContentAsDate();
                 break;
             case "downloads":
                 if (!reader.ReadToDescendant("value", RDF))
                     throw new ApplicationException("Missing download count value.");
                 book.Downloads = reader.ReadElementContentAsInt();
                 break;
             }
         }
     return book;
 }
Exemplo n.º 2
0
 // Parses information about single or multiple persons (authors or contributors) which
 // contain era (year span) of their life. Names of the persons are returned and the
 // era in the book is updated to span across all life spans of all persons.
 string[] ParsePersonsAndEra(Book book, XmlReader reader)
 {
     // Checking the attribute parseType is a quick and dirty way to detect a multivalue
     // property without inspecting the entire element structure and luckily works here.
     var parseType = reader.GetAttribute("parseType", RDF);
     if (parseType == "Literal") {
         var person = reader.ReadElementContentAsString();
         ParsePersonEra(book, person);
         return new[] { person };
     }
     using (var subreader = reader.ReadSubtree())
         return ParseMultiplePersonsAndEra(book, subreader);
 }
Exemplo n.º 3
0
 // Extracts the era of a person's life from the line with the person's name and updates
 // the book so that its era includes the person's one.
 void ParsePersonEra(Book book, string value)
 {
     YearSpan era;
     var comma = value.LastIndexOf(',');
     if (comma > 0 && YearSpan.TryParse(value.Substring(comma + 1).Trim(),
                                         CultureInfo.InvariantCulture, out era))
         book.Era = book.Era.Union(era);
 }
Exemplo n.º 4
0
 // Parses the subtree of multiple persons. It is to be called from the ParsePersonsAndEra
 // method only.
 string[] ParseMultiplePersonsAndEra(Book book, XmlReader reader)
 {
     var persons = new List<string>();
     while (reader.ReadToFollowing("li", RDF)) {
         // So far, I haven't noticed other multivalues than those consisting of literals.
         // When they occur I'll implement better vaue parsing here. Now I save time.
         var parseType = reader.GetAttribute("parseType", RDF);
         if (parseType != "Literal")
             throw new ApplicationException("Unrecognized parse type.");
         string person = reader.ReadElementContentAsString();
         ParsePersonEra(book, person);
         persons.Add(person);
     }
     return persons.Any() ? persons.ToArray() : null;
 }
Exemplo n.º 5
0
 // Gets a book by its name or number if it exists, not throwing and exception if it does
 // not. (If the string contains only digits it will be interpreted as a number.)
 public bool TryGetBook(string name, out Book book)
 {
     int number;
     if (int.TryParse(name, NumberStyles.Integer,
                         CultureInfo.InvariantCulture, out number)) {
         if (number >= 0 && number < BooksByNumber.Length) {
             book = BooksByNumber[number];
             return book != null;
         }
         book = null;
         return false;
     }
     return BooksByName.TryGetValue(name, out book);
 }