显示Unicode字符以HTML转换为PDF显示Unicode字符以HTML转换为PDF(Displ

我使用iTextSharp的DLL到HTML转换为PDF。

该HTML有一些Unicode字符像α，β......当我尝试HTML转换为PDF格式，Unicode字符不是在PDF中。

我的功能：

Document doc = new Document(PageSize.LETTER);

using (FileStream fs = new FileStream(Path.Combine("Test.pdf"), FileMode.Create, FileAccess.Write, FileShare.Read))
{
    PdfWriter.GetInstance(doc, fs);

    doc.Open();
    doc.NewPage();

    string arialuniTff = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Fonts),
                                      "ARIALUNI.TTF");

    BaseFont bf = BaseFont.CreateFont(arialuniTff, BaseFont.IDENTITY_H, BaseFont.EMBEDDED);

    Font fontNormal = new Font(bf, 12, Font.NORMAL);

    List<IElement> list = HTMLWorker.ParseToList(new StringReader(stringBuilder.ToString()),
                                                 new StyleSheet());
    Paragraph p = new Paragraph {Font = fontNormal};

    foreach (var element in list)
    {
        p.Add(element);
        doc.Add(p);
    }

    doc.Close();
}

Answer 1:

当使用Unicode字符和iTextSharp的处理有几件事情你需要照顾。你做第一个已和天色支持您的字符的字体。第二件事是要真正注册iTextSharp的字体，使其意识到这一点。

//Path to our font
string arialuniTff = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Fonts), "ARIALUNI.TTF");
//Register the font with iTextSharp
iTextSharp.text.FontFactory.Register(arialuniTff);

现在，我们有一个字体，我们需要创建一个StyleSheet对象，告诉iTextSharp的何时以及如何使用它。

//Create a new stylesheet
iTextSharp.text.html.simpleparser.StyleSheet ST = new iTextSharp.text.html.simpleparser.StyleSheet();
//Set the default body font to our registered font's internal name
ST.LoadTagStyle(HtmlTags.BODY, HtmlTags.FACE, "Arial Unicode MS");

在一个非HTML部分，你还需要做的是建立一种特殊的encoding参数。这种编码是特定于iTextSharp的和你的情况，你希望它是Identity-H 如果不设置此则默认Cp1252 （ WINANSI ）。

//Set the default encoding to support Unicode characters
ST.LoadTagStyle(HtmlTags.BODY, HtmlTags.ENCODING, BaseFont.IDENTITY_H);

最后，我们需要把我们的样式表传递到ParseToList方法：

//Parse our HTML using the stylesheet created above
List<IElement> list = HTMLWorker.ParseToList(new StringReader(stringBuilder.ToString()), ST);

把所有的一起，从开到关你必须：

doc.Open();

//Sample HTML
StringBuilder stringBuilder = new StringBuilder();
stringBuilder.Append(@"<p>This is a test: <strong>α,β</strong></p>");

//Path to our font
string arialuniTff = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Fonts), "ARIALUNI.TTF");
//Register the font with iTextSharp
iTextSharp.text.FontFactory.Register(arialuniTff);

//Create a new stylesheet
iTextSharp.text.html.simpleparser.StyleSheet ST = new iTextSharp.text.html.simpleparser.StyleSheet();
//Set the default body font to our registered font's internal name
ST.LoadTagStyle(HtmlTags.BODY, HtmlTags.FACE, "Arial Unicode MS");
//Set the default encoding to support Unicode characters
ST.LoadTagStyle(HtmlTags.BODY, HtmlTags.ENCODING, BaseFont.IDENTITY_H);

//Parse our HTML using the stylesheet created above
List<IElement> list = HTMLWorker.ParseToList(new StringReader(stringBuilder.ToString()), ST);

//Loop through each element, don't bother wrapping in P tags
foreach (var element in list) {
    doc.Add(element);
}

doc.Close();

编辑

在你的评论显示HTML，指定替代字体。 iTextSharp的不蜘蛛的系统字体和HTML解析器不使用字体回退技术。在HTML / CSS指定的任何字体，必须手动注册。

string lucidaTff = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Fonts), "l_10646.ttf");
iTextSharp.text.FontFactory.Register(lucidaTff);

Answer 2:

您也可以使用新的XMLWorkerHelper（从库itextsharp.xmlworker），你需要但覆盖默认FontFactory实现。

void GeneratePdfFromHtml()
{
  const string outputFilename = @".\Files\report.pdf";
  const string inputFilename = @".\Files\report.html";

  using (var input = new FileStream(inputFilename, FileMode.Open))
  using (var output = new FileStream(outputFilename, FileMode.Create))
  {
    CreatePdf(input, output);
  }
}

void CreatePdf(Stream htmlInput, Stream pdfOutput)
{
  using (var document = new Document(PageSize.A4, 30, 30, 30, 30))
  {
    var writer = PdfWriter.GetInstance(document, pdfOutput);
    var worker = XMLWorkerHelper.GetInstance();

    document.Open();
    worker.ParseXHtml(writer, document, htmlInput, null, Encoding.UTF8, new UnicodeFontFactory());

    document.Close();
  }    
}

public class UnicodeFontFactory : FontFactoryImp
{
    private static readonly string FontPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Fonts),
      "arialuni.ttf");

    private readonly BaseFont _baseFont;

    public UnicodeFontFactory()
    {
      _baseFont = BaseFont.CreateFont(FontPath, BaseFont.IDENTITY_H, BaseFont.EMBEDDED);

    }

    public override Font GetFont(string fontname, string encoding, bool embedded, float size, int style, BaseColor color,
      bool cached)
    {
      return new Font(_baseFont, size, style, color);
    }
}

Answer 3:

private class UnicodeFontFactory : FontFactoryImp
{
    private BaseFont _baseFont;

    public  UnicodeFontFactory()
    {
        string FontPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Fonts), "arialuni.ttf");
        _baseFont = BaseFont.CreateFont(FontPath, BaseFont.IDENTITY_H, BaseFont.EMBEDDED);                
    }

    public override Font GetFont(string fontname, string encoding, bool embedded, float size, int style, BaseColor color, bool cached)
    {                                
        return new Font(_baseFont, size, style, color);
    }
}

//和代码

FontFactory.FontImp = new UnicodeFontFactory();

string convertedHtml = string.Empty;
foreach (char c in htmlText)
{
     if (c < 127)  
           convertedHtml += c;
     else
           convertedHtml += "&#" + (int)c + ";";
}

List<IElement> htmlElements = XMLWorkerHelper.ParseToElementList(convertedHtml, null);

// add the IElements to the document
foreach (IElement htmlElement in htmlElements)
{                            
      document.Add(htmlElement);
}

Answer 4:

这必须是的，我已经有弄清楚迄今为止最困难的问题之一。在网络上的答案，包括堆栈溢出很差或者过时的信息。从格雷戈尔答案是非常接近的。我希望自己能回馈这个社会，因为我花了很多时间去这个答案。

这里是一个非常简单的程序，我在C＃中写道：作为我自己的笔记的例子。

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using iTextSharp.text;
using iTextSharp.text.pdf;
using iTextSharp.tool.xml;

namespace ExampleOfExportingPDF
{
    class Program
    {
        static void Main(string[] args)
        {
            //Build HTML document
            StringBuilder sb = new StringBuilder();
            sb.Append("<body>");
            sb.Append("<h1 style=\"text-align:center;\">これは日本語のテキストの例です。</h1>");
            sb.Append("</body>");

            //Create our document object
            Document Doc = new Document(PageSize.A4);


            //Create our file stream
            using (FileStream fs = new FileStream(Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Desktop), "Test.pdf"), FileMode.Create, FileAccess.Write, FileShare.Read))
            {
                //Bind PDF writer to document and stream
                PdfWriter writer = PdfWriter.GetInstance(Doc, fs);

                //Open document for writing
                Doc.Open();


                //Add a page
                Doc.NewPage();

                MemoryStream msHtml = new MemoryStream(System.Text.Encoding.UTF8.GetBytes(sb.ToString()));
                XMLWorkerHelper.GetInstance().ParseXHtml(writer, Doc, msHtml, null, Encoding.UTF8, new UnicodeFontFactory());

                //Close the PDF
                Doc.Close();
            }

        }

        public class UnicodeFontFactory : FontFactoryImp
        {
            private static readonly string FontPath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.Fonts),
          "arialuni.ttf");

            private readonly BaseFont _baseFont;

            public UnicodeFontFactory()
            {
                _baseFont = BaseFont.CreateFont(FontPath, BaseFont.IDENTITY_H, BaseFont.EMBEDDED);

            }

            public override Font GetFont(string fontname, string encoding, bool embedded, float size, int style, BaseColor color,
          bool cached)
            {
                return new Font(_baseFont, size, style, color);
            }
        }

    }
}

希望这将节省别人在未来的一段时间。