How do you place HTML in a table cell while creating a new PDF with iText7?

Question

I'm creating a PDF with a large table on it. In this table, there's a cell that can be filled in with HTML. If it is, the HTML must be interpreted as HTML and not be shown as regular text. However, when I do so, the layout/style gets scrambled and some pictures don't get shown. (In the example I give, the bullet dashes are replaced by 9's.)

I program in C# and am using iText7 to create the PDF.

In my project, I have the following HTML Code that I want to show. The reason the HTML code looks like this is because it's RTF converted to HTML:






Untitled document




 

Dishwasher soap container consumption is adjusted

Power UP ballast water treatmant unit, adjusted what necessary. GPS signal error still pending

Installed new insect killer in galley

Adjust securing and highest ladder position after its tilted to low trunnion position

SW spooling device test is done and no isses 

Sewage unit dosage pump; make permanent installation + drawing update

Intervention on DN203: installed tracker box on ICT request

Installed tracker box on ICT request 

Regular greasing emotors according ship specific grease list

Regular maintenance of portable tools

Intervention on DN203 due to problem with SB M/E

When I save this file as a HTML file and open it in a browser, you get the following result (which is correct): Correct result (website)

However, when I add it to the PDF cell, I get the following result: Bad result (PDF)

As you can see, the dashes used for bulleting have turned into 9's.

The code I use to add the HTML code to the PDF File is the following:

private void AddCellToTable(table table, string HTMLContent) {
    Cell newCell = new Cell();

    foreach (var element in HtmlConverter.ConvertToElements(HTMLContent))
    {
        var test = (IBlockElement)element;
        newCell.Add(test);
    }

    table.AddCell(newCell);
 }

This code is similar to the code suggested by https://itextpdf.com/en/resources/books/itext-7-converting-html-pdf-pdfhtml/chapter-1-hello-html-pdf (They use java instead of C#).

I would like to show bullets as dashes, instead of these 9's. Any help or suggestions would be very much appreciated.

Thank you in advance.

user_6663375 · Answer

Firstly, the problem isn't related to layout (table/cell/etc processing) - it's only about fonts and how iText processes them.

Secondly, the problem is that PDF's standard Symbol font, which is used by iText, differs from the one used by browsers.

Thirdly, iText doesn't processes "\F02D\9" (and "\9" part in particular) correctly.

What can you do to improve the resultant pdf? Don't use the standard PDF's Symbol font - use your own Symbol font instead.

How to do it?

Let me introduce you the FontProvider class.

FontProvider is responsible to handle the fonts which may be used while processing an html file. Its instance could be passed as a parameter of ConverterProperties, otherwise it'd be created by iText. By default iText adds to FontProvider all standard pdf fonts (FontProvider#addStandardPdfFonts) and some free sans fonts (DefaultFontProvider#SHIPPED_FONT_NAMES).

You want to use your own Symbol font: that means that you should prevent iText from considering standard Symbol font during convertion. To do so, please create a DefaultFontProvider instance with the first constructor's argument passed as false. (!) In 99% of the cases you want some other standard fonts to be considerd during convertion. So please add them manually as follows:

provider.addFont(StandardFonts.TIMES_ROMAN);
// some other fonts to be added

Now add your own Symbol font to this FontProvider instance the same way as I did it for the Times above:

provider.addFont("C:\Windows\Fonts\symbol.ttf", PdfEncodings.IDENTITY_H);

It's important to use IDENTITY_H there, because in the Symbol font "-" has "F02D" as its unicode value.

After all these changes, I've managed to get the following file:

Now comes the second problem: iText doesn't process "\9" by default correctly. As for this one, I don't know any straight-forward solution. Probably, removing it from your html is the best one.

How do you place HTML in a table cell while creating a new PDF with iText7?

1 Answers