namespace Utils
{
    public class BookInfo
    {
        public static book GetBookByISBN(string isbn)
        {
            //这是自定义的一个图书类book对象
            book books = new book();
            try
            {
                //创建所需HTTP服务对象
                HttpWebRequest myRequest = null;
                HttpWebResponse myHttpResponse = null;
                //豆瓣的获取图书信息的地址
                string doubanurl = "http://api.douban.com/book/subject/isbn/";
                //将图书的isbn号和申请的apikey添加到豆瓣获取图书地址的后面  
                //注意：?apikey=0400ce550f5955da0c026aff2e0c018e是为了使每分钟能够访问更多的次数
                //可以没有，不过没有默认为每分钟访问10次，申请的话，可到豆瓣API的使用方法中了解
                string geturl = doubanurl + isbn+"?apikey=0400ce550f5955da0c026aff2e0c018e";
                //为Http服务对象实例化
                myRequest = (HttpWebRequest)WebRequest.Create(geturl);
                myHttpResponse = (HttpWebResponse)myRequest.GetResponse();
                //获取网页流
                StreamReader reader = new StreamReader(myHttpResponse.GetResponseStream());
                //读取网页中的信息
                string xmldetail = reader.ReadToEnd();
                //关闭读取流
                reader.Close();
                //关闭Http服务
                myHttpResponse.Close();

                //除了book对象，下面的代码转至：http://www.cnblogs.com/sun8134/archive/2010/12/15/1906879.html
                XmlDocument xml = new XmlDocument();
                xml.LoadXml(xmldetail);
                XmlNamespaceManager nsmgr = new XmlNamespaceManager(xml.NameTable);
                nsmgr.AddNamespace("db", "http://www.w3.org/2005/Atom");
                XmlElement root = xml.DocumentElement;
                XmlNodeList nodes = root.SelectNodes("/db:entry", nsmgr);

                foreach (XmlNode nodeData in nodes)
                {
                    foreach (XmlNode childnode in nodeData.ChildNodes)
                    {
                        string str = childnode.Name;
                        switch (str)
                        {
                            case "title":
                                books.B_NAME = childnode.InnerText;
                                break;
                            case "link":
                                if (childnode.Attributes[1].Value == "image")
                                {
                                    books.ImageURL = childnode.Attributes[0].Value;
                                }
                                break;
                            case "summary":
                                books.B_SUMMARY = childnode.InnerText;
                                break;
                            case "db:attribute":
                                {
                                    switch (childnode.Attributes[0].Value)
                                    {
                                        case "isbn13":
                                            books.B_ISBN = childnode.InnerText;
                                            break;
                                        case "pages":
                                            books.B_PAGE_NUM = childnode.InnerText;
                                            break;
                                        case "author":
                                            books.B_Author = childnode.InnerText;
                                            break;
                                        case "price":
                                            books.B_PRICE = childnode.InnerText;
                                            break;
                                        case "publisher":
                                            books.B_Publisher = childnode.InnerText;
                                            break;
                                        case "pubdate":
                                            books.B_PubTime = childnode.InnerText;
                                            break;
                                    }//end switch
                                    break;
                                }
                        }//end switch
                    }//end foreach
                }//end foreach
            }
            catch (Exception ex)
            {
            }
            return books;

        }
    }
}

public class book
    {
        public int B_ID { get; set; }

        public string  B_NO { get; set; }

        public string  B_NAME { get; set; }

        public string B_CG_NO { get; set; }

        public string B_INDEX_NO { get; set; }

        public string B_PAGE_NUM { get; set; }

        public string B_NUM { get; set; }

        public string B_PRICE { get; set; }

        public string B_Author { get; set; }

        public string  B_Publisher { get; set; }

        public string B_PubTime { get; set; }

        public string B_ISBN { get; set; }

        public string B_SUMMARY { get; set; }

        //额外
        public string ImageURL { get; set; }
    }