Delphi WkHtmlToX Library

Delphi implementation of WkHtmlToX.

What is it?

WkHtmlToPdf is an open source (LGPLv3) command line tool and a C API (WkHtmlToX) to render HTML into PDF using the Qt WebKit rendering engine. These run entirely "headless" and do not require a display or display service.

Delphi WkHtmlToX Library is an open source (Apache license) wrapper around WkHtmlToX. You can find a basic header traslation from the C API (WkHtmlToX.Bindings.pas) and few classes that simplify its usage (WkHtmlToX.Core.pas).

Inside the samples folder you can find 4 demos:

• ApiDemo: a simple example that convert a HTML using only the raw API
• WrapperDemo: same as before but with IWkHtmlToPdf class
• ThreadedDemo: a thread-safe sample
• StreamDemo: another example using HTML from memory instead of file

WkHtmlToX has several configuration options, you can find a comprehensive list on the original documentation page.

Usage

Source code:

var
  ObjectSettings: IWkObjectSettings;
  GlobalSettings: IWkGlobalSettings;
  Converter: IWkConverter;
begin
  GlobalSettings := WkHtmlToPdf.CreateGlobalSettings;
  // We want the result to be storred in the file called test.pdf 
  GlobalSettings['out'] := 'test.pdf';

  ObjectSettings := WkHtmlToPdf.CreateObjectSettings;
  // We want to convert the url 'https://wkhtmltopdf.org/'
  ObjectSettings['page'] := 'https://wkhtmltopdf.org/';

  Converter := WkHtmlToPdf.CreateConverter(GlobalSettings);
  // Add the settings object to the list of pages to convert. 
  // Objects are converted in the order in which they are added
  Converter.AddObject(ObjectSettings);

  Converter.Convert;
end;

You can find the GlobalSettings and ObjectSettings reference guide here: https://wkhtmltopdf.org/libwkhtmltox/pagesettings.html

Issues

• CharSet: in-memory Html conversion doesn't support unicode. You can use metatag as a work-around (see StreamDemo) or use HTML Entities.
• Thread-safety: the tool can convert only a document at once. You can find a work-around in the ThreadDemo.

Prerequisite

WkHtmlToX library must be in your system path.