public async Task <EbookPageModel> FindEbookUrl(EbookPageModel webPageModel)
{
string html;
try
{
html = await HttpDownloader.DownloadHtmlPage(webPageModel.Url);
}
catch
{
throw;
}
IBrowsingContext context = BrowsingContext.New();
IDocument document = await context.OpenAsync(response => response.Content(html));
IEnumerable <IElement> downloadLinkElements = document.QuerySelectorAll("span.download-links");
if (downloadLinkElements.Count() == 0)
{
throw new TargetNotFindException("无法在HTML中找到下载链接");
}
IElement detail = document.QuerySelector("div.book-detail");
IEnumerable <IElement> terms = detail.QuerySelectorAll("dd");
IEnumerable <IElement> authorsElements = terms.ElementAt(0).QuerySelectorAll("a");
webPageModel.Author = string.Join(";", authorsElements.Select(x => x.InnerHtml));
webPageModel.ISBN = terms.ElementAt(1).InnerHtml;
webPageModel.Year = Int32.Parse(terms.ElementAt(2).InnerHtml);
webPageModel.Pages = Int32.Parse(terms.ElementAt(3).InnerHtml);
webPageModel.Language = terms.ElementAt(4).InnerHtml;
webPageModel.FileSize = terms.ElementAt(5).InnerHtml;
//webPageModel.FileFormat = terms.ElementAt(6).InnerHtml;
IEnumerable <IElement> tagElements = terms.ElementAt(7).QuerySelectorAll("a");
webPageModel.Category = string.Join(";", tagElements.Select(x => x.InnerHtml));
webPageModel.Description = document.QuerySelector("div.entry-content").InnerHtml;
webPageModel.Title = document.QuerySelector("h1.single-title").InnerHtml;
IElement subTitleElement = document.QuerySelector("h4");
if (subTitleElement != null)
{
webPageModel.SubTitle = subTitleElement.InnerHtml;
}
IElement imageElement = document.QuerySelector("header.entry-header");
IElement imageElement1 = imageElement.QuerySelector("img");
string imageUrl = imageElement1.GetAttribute("src");
string fileUniqueName = TimeHelper.GetTimeStamp();
webPageModel.Image = new EbookImageModel(fileUniqueName, imageUrl);
List <EbookFileModel> ebooks = new List <EbookFileModel>();
int i = 1;
foreach (Element downloadLinkElement in downloadLinkElements)
{
string url = downloadLinkElement.QuerySelector("a").GetAttribute("href");
string fileName = fileUniqueName + "_" + i;
ebooks.Add(new EbookFileModel(webPageModel, url, fileName));
i++;
//Debug.WriteLine("fileName=" + fileName);
}
webPageModel.EBooks = ebooks;
return(webPageModel);
}
private static async Task ParseAndDownload(EbookPageModel webpage)
{
EbookPageModel page = await parser.FindEbookUrl(webpage);
//下载图书文件
int success = 0;
foreach (EbookFileModel ebook in page.EBooks)
{
try
{
byte[] file = await HttpDownloader.DownloadBytes(ebook.DownloadUrl);
FileWriter.WriteToFile(file, ebook.FileSavePath);
success++;
ebook.IsDownloaded = true;
DownloadFileCount++;
Debug.WriteLine("下载文件数量=" + DownloadFileCount);
}
catch (TaskCanceledException)
{
Debug.WriteLine("下载图书文件超时");
continue;
}
catch (HttpRequestException e)
{
Debug.WriteLine("访问图书下载连接失败：" + e.Message);
continue;
}
catch (Exception e)
{
Debug.WriteLine(e.Message);
continue;
}
}
if (success == 0)
{
return;
}
//下载图书图片
try
{
byte[] imageBytes = await HttpDownloader.DownloadBytes(page.Image.ImageUrl);
FileWriter.WriteToFile(imageBytes, page.Image.ImageSavePath);
//如果图片下载成功，则填入地址，失败则为null
page.ImagePath = page.Image.ImageSavePath;
}
catch (TaskCanceledException)
{
Debug.WriteLine("下载图片超时");
}
catch (HttpRequestException e)
{
Debug.WriteLine("访问图片连接失败：" + e.Message);
}
catch (Exception e)
{
Debug.WriteLine(e.Message);
}
//添加对象属性
page.FilePaths = string.Join(", ", page.EBooks.Where(x => x.IsDownloaded).Select(x => x.FileSavePath));
page.FileFormat = string.Join(", ", page.EBooks.Where(x => x.IsDownloaded).Select(x => x.FileExtention));
page.FileCount = page.EBooks.Where(x => x.IsDownloaded).Count();
//写入数据库
//using (var db=new MyAppDbContext())
//{
// db.Blogs.Add(page);
// db.SaveChanges();
// RecordCount++;
// Debug.WriteLine("写入记录条数=" + RecordCount);
//}
}
