问题
I\'d like to know if ITextSharp has the capability of converting HTML to PDF. Everything I will convert will just be plain text but unfortunately there is very little to no documentation on ITextSharp so I can\'t determine if that will be a viable solution for me.
If it can\'t do it, can someone point me to some good, free .net libraries that can take a simple plain text HTML document and convert it to a pdf?
tia.
回答1:
I came across the same question a few weeks ago and this is the result from what I found. This method does a quick dump of HTML to a PDF. The document will most likely need some format tweaking.
private MemoryStream createPDF(string html)
{
MemoryStream msOutput = new MemoryStream();
TextReader reader = new StringReader(html);
// step 1: creation of a document-object
Document document = new Document(PageSize.A4, 30, 30, 30, 30);
// step 2:
// we create a writer that listens to the document
// and directs a XML-stream to a file
PdfWriter writer = PdfWriter.GetInstance(document, msOutput);
// step 3: we create a worker parse the document
HTMLWorker worker = new HTMLWorker(document);
// step 4: we open document and start the worker on the document
document.Open();
worker.StartDocument();
// step 5: parse the html into the document
worker.Parse(reader);
// step 6: close the document and the worker
worker.EndDocument();
worker.Close();
document.Close();
return msOutput;
}
回答2:
after doing some digging I found a good way to accomplish what I need with ITextSharp.
Here is some sample code if it will help anyone else in the future:
protected void Page_Load(object sender, EventArgs e)
{
Document document = new Document();
try
{
PdfWriter.GetInstance(document, new FileStream("c:\\my.pdf", FileMode.Create));
document.Open();
WebClient wc = new WebClient();
string htmlText = wc.DownloadString("http://localhost:59500/my.html");
Response.Write(htmlText);
List<IElement> htmlarraylist = HTMLWorker.ParseToList(new StringReader(htmlText), null);
for (int k = 0; k < htmlarraylist.Count; k++)
{
document.Add((IElement)htmlarraylist[k]);
}
document.Close();
}
catch
{
}
}
回答3:
Here's what I was able to get working on version 5.4.2 (from the nuget install) to return a pdf response from an asp.net mvc controller. It could be modfied to use a FileStream instead of MemoryStream for the output if that's what is needed.
I post it here because it is a complete example of current iTextSharp usage for the html -> pdf conversion (disregarding images, I haven't looked at that since my usage doesn't require it)
It uses iTextSharp's XmlWorkerHelper, so the incoming hmtl must be valid XHTML, so you may need to do some fixup depending on your input.
using iTextSharp.text.pdf;
using iTextSharp.tool.xml;
using System.IO;
using System.Web.Mvc;
namespace Sample.Web.Controllers
{
public class PdfConverterController : Controller
{
[ValidateInput(false)]
[HttpPost]
public ActionResult HtmlToPdf(string html)
{
html = @"<?xml version=""1.0"" encoding=""UTF-8""?>
<!DOCTYPE html
PUBLIC ""-//W3C//DTD XHTML 1.0 Strict//EN""
""http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"">
<html xmlns=""http://www.w3.org/1999/xhtml"" xml:lang=""en"" lang=""en"">
<head>
<title>Minimal XHTML 1.0 Document with W3C DTD</title>
</head>
<body>
" + html + "</body></html>";
var bytes = System.Text.Encoding.UTF8.GetBytes(html);
using (var input = new MemoryStream(bytes))
{
var output = new MemoryStream(); // this MemoryStream is closed by FileStreamResult
var document = new iTextSharp.text.Document(iTextSharp.text.PageSize.LETTER, 50, 50, 50, 50);
var writer = PdfWriter.GetInstance(document, output);
writer.CloseStream = false;
document.Open();
var xmlWorker = XMLWorkerHelper.GetInstance();
xmlWorker.ParseXHtml(writer, document, input, null);
document.Close();
output.Position = 0;
return new FileStreamResult(output, "application/pdf");
}
}
}
}
回答4:
I would one-up'd mightymada's answer if I had the reputation - I just implemented an asp.net HTML to PDF solution using Pechkin. results are wonderful.
There is a nuget package for Pechkin, but as the above poster mentions in his blog (http://codeutil.wordpress.com/2013/09/16/convert-html-to-pdf/ - I hope she doesn't mind me reposting it), there's a memory leak that's been fixed in this branch:
https://github.com/tuespetre/Pechkin
The above blog has specific instructions for how to include this package (it's a 32 bit dll and requires .net4). here is my code. The incoming HTML is actually assembled via HTML Agility pack (I'm automating invoice generations):
public static byte[] PechkinPdf(string html)
{
//Transform the HTML into PDF
var pechkin = Factory.Create(new GlobalConfig());
var pdf = pechkin.Convert(new ObjectConfig()
.SetLoadImages(true).SetZoomFactor(1.5)
.SetPrintBackground(true)
.SetScreenMediaType(true)
.SetCreateExternalLinks(true), html);
//Return the PDF file
return pdf;
}
again, thank you mightymada - your answer is fantastic.
回答5:
I prefer using another library called Pechkin because it is able to convert non trivial HTML (that also has CSS classes). This is possible because this library uses the WebKit layout engine that is also used by browsers like Chrome and Safari.
I detailed on my blog my experience with Pechkin: http://codeutil.wordpress.com/2013/09/16/convert-html-to-pdf/
回答6:
The above code will certainly help in converting HTML to PDF but will fail if the the HTML code has IMG tags with relative paths. iTextSharp library does not automatically convert relative paths to absolute ones.
I tried the above code and added code to take care of IMG tags too.
You can find the code here for your reference: http://www.am22tech.com/html-to-pdf/
回答7:
It has ability to convert HTML file in to pdf.
Required namespace for conversions are:
using iTextSharp.text;
using iTextSharp.text.pdf;
and for conversion and download file :
// Create a byte array that will eventually hold our final PDF
Byte[] bytes;
// Boilerplate iTextSharp setup here
// Create a stream that we can write to, in this case a MemoryStream
using (var ms = new MemoryStream())
{
// Create an iTextSharp Document which is an abstraction of a PDF but **NOT** a PDF
using (var doc = new Document())
{
// Create a writer that's bound to our PDF abstraction and our stream
using (var writer = PdfWriter.GetInstance(doc, ms))
{
// Open the document for writing
doc.Open();
string finalHtml = string.Empty;
// Read your html by database or file here and store it into finalHtml e.g. a string
// XMLWorker also reads from a TextReader and not directly from a string
using (var srHtml = new StringReader(finalHtml))
{
// Parse the HTML
iTextSharp.tool.xml.XMLWorkerHelper.GetInstance().ParseXHtml(writer, doc, srHtml);
}
doc.Close();
}
}
// After all of the PDF "stuff" above is done and closed but **before** we
// close the MemoryStream, grab all of the active bytes from the stream
bytes = ms.ToArray();
}
// Clear the response
Response.Clear();
MemoryStream mstream = new MemoryStream(bytes);
// Define response content type
Response.ContentType = "application/pdf";
// Give the name of file of pdf and add in to header
Response.AddHeader("content-disposition", "attachment;filename=invoice.pdf");
Response.Buffer = true;
mstream.WriteTo(Response.OutputStream);
Response.End();
回答8:
If you are converting html to pdf on the html server side you can use Rotativa :
Install-Package Rotativa
This is based on wkhtmltopdf but it has better css support than iTextSharp has and is very simple to integrate with MVC (which is mostly used) as you can simply return the view as pdf:
public ActionResult GetPdf()
{
//...
return new ViewAsPdf(model);// and you are done!
}
来源：https://stackoverflow.com/questions/2822843/itextsharp-html-to-pdf