我想通过将HTML内容传递给函数来生成PDF。我已经为此使用了iTextSharp,但它在遇到表和布局时表现不佳。
有没有更好的办法?
我想通过将HTML内容传递给函数来生成PDF。我已经为此使用了iTextSharp,但它在遇到表和布局时表现不佳。
有没有更好的办法?
当前回答
如果你已经使用itextsharp dll,不需要添加第三方dll的(插件),我认为你正在使用htmlworker而不是它使用xmlworker,你可以很容易地将你的html转换为pdf。 一些css不能工作,他们是受支持的css 完整的解释与示例参考点击这里
MemoryStream memStream = new MemoryStream();
TextReader xmlString = new StringReader(outXml);
using (Document document = new Document())
{
PdfWriter writer = PdfWriter.GetInstance(document, memStream);
//document.SetPageSize(iTextSharp.text.PageSize.A4);
document.Open();
byte[] byteArray = System.Text.Encoding.UTF8.GetBytes(outXml);
MemoryStream ms = new MemoryStream(byteArray);
XMLWorkerHelper.GetInstance().ParseXHtml(writer, document, ms, System.Text.Encoding.UTF8);
document.Close();
}
Response.ContentType = "application/pdf";
Response.AddHeader("content-disposition", "attachment;filename=" + filename + ".pdf");
Response.Cache.SetCacheability(HttpCacheability.NoCache);
Response.BinaryWrite(memStream.ToArray());
Response.End();
Response.Flush();
其他回答
下面是一个使用iTextSharp将html + css转换为PDF的示例(iTextSharp + iTextSharp .xmlworker)
using iTextSharp.text;
using iTextSharp.text.pdf;
using iTextSharp.tool.xml;
byte[] pdf; // result will be here
var cssText = File.ReadAllText(MapPath("~/css/test.css"));
var html = File.ReadAllText(MapPath("~/css/test.html"));
using (var memoryStream = new MemoryStream())
{
var document = new Document(PageSize.A4, 50, 50, 60, 60);
var writer = PdfWriter.GetInstance(document, memoryStream);
document.Open();
using (var cssMemoryStream = new MemoryStream(System.Text.Encoding.UTF8.GetBytes(cssText)))
{
using (var htmlMemoryStream = new MemoryStream(System.Text.Encoding.UTF8.GetBytes(html)))
{
XMLWorkerHelper.GetInstance().ParseXHtml(writer, document, htmlMemoryStream, cssMemoryStream);
}
}
document.Close();
pdf = memoryStream.ToArray();
}
很可能大多数项目将包装C/ c++引擎,而不是从头开始实现c#解决方案。试试哥德堡计划。
为了测试它
docker run --rm -p 3000:3000 thecodingmachine/gotenberg:6
旋度样本
curl --request POST \
--url http://localhost:3000/convert/url \
--header 'Content-Type: multipart/form-data' \
--form remoteURL=https://brave.com \
--form marginTop=0 \
--form marginBottom=0 \
--form marginLeft=0 \
--form marginRight=0 \
-o result.pdf
c# sample.cs
using System;
using System.Net.Http;
using System.Threading.Tasks;
using System.IO;
using static System.Console;
namespace Gotenberg
{
class Program
{
public static async Task Main(string[] args)
{
try
{
var client = new HttpClient();
var formContent = new MultipartFormDataContent
{
{new StringContent("https://brave.com/"), "remoteURL"},
{new StringContent("0"), "marginTop" }
};
var result = await client.PostAsync(new Uri("http://localhost:3000/convert/url"), formContent);
await File.WriteAllBytesAsync("brave.com.pdf", await result.Content.ReadAsByteArrayAsync());
}
catch (Exception ex)
{
WriteLine(ex);
}
}
}
}
要编译
csc sample.cs -langversion:latest -reference:System.Net.Http.dll && mono ./sample.exe
你可以使用WebBrowser控件的另一个技巧,下面是我的完整工作代码
在我的例子中,为文本框控件分配Url
protected void Page_Load(object sender, EventArgs e)
{
txtweburl.Text = "https://www.google.com/";
}
下面是使用线程生成屏幕的代码
protected void btnscreenshot_click(object sender, EventArgs e)
{
// btnscreenshot.Visible = false;
allpanels.Visible = true;
Thread thread = new Thread(GenerateThumbnail);
thread.SetApartmentState(ApartmentState.STA);
thread.Start();
thread.Join();
}
private void GenerateThumbnail()
{
// btnscreenshot.Visible = false;
WebBrowser webrowse = new WebBrowser();
webrowse.ScrollBarsEnabled = false;
webrowse.AllowNavigation = true;
string url = txtweburl.Text.Trim();
webrowse.Navigate(url);
webrowse.Width = 1400;
webrowse.Height = 50000;
webrowse.DocumentCompleted += webbrowse_DocumentCompleted;
while (webrowse.ReadyState != WebBrowserReadyState.Complete)
{
System.Windows.Forms.Application.DoEvents();
}
}
在下面的代码中,我下载后保存pdf文件
private void webbrowse_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
// btnscreenshot.Visible = false;
string folderPath = Server.MapPath("~/ImageFiles/");
WebBrowser webrowse = sender as WebBrowser;
//Bitmap bitmap = new Bitmap(webrowse.Width, webrowse.Height);
Bitmap bitmap = new Bitmap(webrowse.Width, webrowse.Height, PixelFormat.Format16bppRgb565);
webrowse.DrawToBitmap(bitmap, webrowse.Bounds);
string Systemimagedownloadpath = System.Configuration.ConfigurationManager.AppSettings["Systemimagedownloadpath"].ToString();
string fullOutputPath = Systemimagedownloadpath + Request.QueryString["VisitedId"].ToString() + ".png";
MemoryStream stream = new MemoryStream();
bitmap.Save(fullOutputPath, System.Drawing.Imaging.ImageFormat.Jpeg);
//generating pdf code
Document pdfDoc = new Document(new iTextSharp.text.Rectangle(1100f, 20000.25f));
PdfWriter writer = PdfWriter.GetInstance(pdfDoc, Response.OutputStream);
pdfDoc.Open();
iTextSharp.text.Image img = iTextSharp.text.Image.GetInstance(fullOutputPath);
img.ScaleAbsoluteHeight(20000);
img.ScaleAbsoluteWidth(1024);
pdfDoc.Add(img);
pdfDoc.Close();
//Download the PDF file.
Response.ContentType = "application/pdf";
Response.AddHeader("content-disposition", "attachment;filename=ImageExport.pdf");
Response.Cache.SetCacheability(HttpCacheability.NoCache);
Response.Write(pdfDoc);
Response.End();
}
你也可以参考我最老的帖子了解更多信息:在asp.net web表单中导航到网页被取消了
最后更新:2020年10月
这是我整理的。net中HTML到PDF转换的选项列表(有些是免费的,有些是付费的)
GemBox.Document https://www.nuget.org/packages/GemBox.Document/ Free (up to 20 paragraphs) $680 - https://www.gemboxsoftware.com/document/pricelist https://www.gemboxsoftware.com/document/examples/c-sharp-convert-html-to-pdf/307 PDF Metamorphosis .Net https://www.nuget.org/packages/sautinsoft.pdfmetamorphosis/ $539 - $1078 - https://www.sautinsoft.com/products/pdf-metamorphosis/order.php https://www.sautinsoft.com/products/pdf-metamorphosis/convert-html-to-pdf-dotnet-csharp.php HtmlRenderer.PdfSharp https://www.nuget.org/packages/HtmlRenderer.PdfSharp/1.5.1-beta1 BSD-UNSPECIFIED License PuppeteerSharp https://www.puppeteersharp.com/examples/index.html MIT License https://github.com/kblok/puppeteer-sharp EO.Pdf https://www.nuget.org/packages/EO.Pdf/ $799 - https://www.essentialobjects.com/Purchase.aspx?f=3 WnvHtmlToPdf_x64 https://www.nuget.org/packages/WnvHtmlToPdf_x64/ $750 - $1600 - http://www.winnovative-software.com/Buy.aspx demo - http://www.winnovative-software.com/demo/default.aspx IronPdf https://www.nuget.org/packages/IronPdf/ $399 - $1599 - https://ironpdf.com/licensing/ https://ironpdf.com/examples/using-html-to-create-a-pdf/ Spire.PDF https://www.nuget.org/packages/Spire.PDF/ Free (up to 10 pages) $599 - $1799 - https://www.e-iceblue.com/Buy/Spire.PDF.html https://www.e-iceblue.com/Tutorials/Spire.PDF/Spire.PDF-Program-Guide/Convert-HTML-to-PDF-Customize-HTML-to-PDF-Conversion-by-Yourself.html Aspose.Html https://www.nuget.org/packages/Aspose.Html/ $599 - $1797 - https://purchase.aspose.com/pricing/html/net https://docs.aspose.com/html/net/html-to-pdf-conversion/ EvoPDF https://www.nuget.org/packages/EvoPDF/ $450 - $1200 - http://www.evopdf.com/buy.aspx ExpertPdfHtmlToPdf https://www.nuget.org/packages/ExpertPdfHtmlToPdf/ $550 - $1200 - https://www.html-to-pdf.net/Pricing.aspx Zetpdf https://zetpdf.com $299 - $599 - https://zetpdf.com/pricing/ Is not a well know or supported library - ZetPDF - Does anyone know the background of this Product? PDFtron https://www.pdftron.com/documentation/samples/cs/HTML2PDFTes $4000/year - https://www.pdftron.com/licensing/ WkHtmlToXSharp https://github.com/pruiz/WkHtmlToXSharp Free Concurrent conversion is implemented as processing queue. SelectPDF https://www.nuget.org/packages/Select.HtmlToPdf/ Free (up to 5 pages) $499 - $799 - https://selectpdf.com/pricing/ https://selectpdf.com/pdf-library-for-net/
如果上面的选项都帮不了你,你可以搜索NuGet包: https://www.nuget.org/packages?q=html+pdf
不是直接将HTML解析为PDF,而是可以创建HTML页面的位图,然后将位图插入到PDF中,例如使用iTextSharp。
这是一个代码如何获得一个URL的位图。我在这里找到了它,如果我找到了源,我会链接它。
public System.Drawing.Bitmap HTMLToImage(String strHTML)
{
System.Drawing.Bitmap myBitmap = null;
System.Threading.Thread myThread = new System.Threading.Thread(delegate()
{
// create a hidden web browser, which will navigate to the page
System.Windows.Forms.WebBrowser myWebBrowser = new System.Windows.Forms.WebBrowser();
// we don't want scrollbars on our image
myWebBrowser.ScrollBarsEnabled = false;
// don't let any errors shine through
myWebBrowser.ScriptErrorsSuppressed = true;
// let's load up that page!
myWebBrowser.Navigate("about:blank");
// wait until the page is fully loaded
while (myWebBrowser.ReadyState != System.Windows.Forms.WebBrowserReadyState.Complete)
System.Windows.Forms.Application.DoEvents();
myWebBrowser.Document.Body.InnerHtml = strHTML;
// set the size of our web browser to be the same size as the page
int intScrollPadding = 20;
int intDocumentWidth = myWebBrowser.Document.Body.ScrollRectangle.Width + intScrollPadding;
int intDocumentHeight = myWebBrowser.Document.Body.ScrollRectangle.Height + intScrollPadding;
myWebBrowser.Width = intDocumentWidth;
myWebBrowser.Height = intDocumentHeight;
// a bitmap that we will draw to
myBitmap = new System.Drawing.Bitmap(intDocumentWidth - intScrollPadding, intDocumentHeight - intScrollPadding);
// draw the web browser to the bitmap
myWebBrowser.DrawToBitmap(myBitmap, new System.Drawing.Rectangle(0, 0, intDocumentWidth - intScrollPadding, intDocumentHeight - intScrollPadding));
});
myThread.SetApartmentState(System.Threading.ApartmentState.STA);
myThread.Start();
myThread.Join();
return myBitmap;
}