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The Winnovative HTML to PDF Converter and the Winnovative PDF Creator products allow
a very fine control of the PDF rendering process. The default settings of the converter
should be acceptable for majority of the situations but sometimes more control and
customizations is necessary.
PDF Document Page Orientation
You can set the PDF document page orientation to Portrait or Landscape. By default
the document page is A4 size Portrait orientation. To change the page orientation
to Landscape you have to set the PdfConverter.PdfDocumentOptions.PdfPageOrientation
property in HTML to PDF Converter or you can set the PDF page orientation when you
create a PDF page with PDF Creator. All the pages auto generated by the PDF
Creator during conversion will have the same orientation with the page where the
HtmlToPdfElement was placed.
With HTML to PDF Converter for .NET library you can set the landscape orientation
with:
PdfConverter.PdfDocumentOptions.PdfPageOrientation
= PDFPageOrientation.Landscape
and with PDF Creator for .NET library you can create a new landscape page with :
Document.Pages.AddNewPage(PageSize.A4,
new Margins(10,10,0, 0), PageOrientation.landscape)
PDF Document Page Size
You can set the PDF page size to a standard size like A4, A3, etc. or you can set
the PDF page size to a custom value. The custom page size width and height are specified
in points (1 point is 1/72 inches).
With the HTML to PDF Converter for .NET library you can set the PDF page size to
a standard value with:
PdfConverter.PdfDocumentOptions.PdfPageSize
= PdfPageSize.A4
or a custom value with:
PdfConverter.PdfDocumentOptions.PdfPageSize
= PdfPageSize.Custom
PdfConverter.PdfDocumentOptions.CustomPdfPageSize
= new SizeF(widthInPoints, heightInPoints)
With the PDF Creator for .NET library you can set the PDF page size to a standard
value with:
Document.Pages.AddNewPage(PageSize.A4,
new Margins(10,10,0, 0), PageOrientation.landscape)
or a custom value with:
Document.Pages.AddNewPage(new PageSize(widthInPoints,
widthInPoints), new Margins(10,10,0, 0), PageOrientation.landscape)
HTML to PDF Converter Virtual Display
The converter internally uses a virtual display where to render the HTML page very
similar to what the web browser does on the screen. The virtual display resolution
is given by the Windows DPI currently set in the display properties in Windows Control
Panel. The default Windows DPI is 96 dpi (dots per inch). The web page elements
dimensions are usually measured in pixels and this is the reason why the virtual
display of the converter is also specified in pixels. These are the only dimensions
used by the converter which are expressed in pixels. All the other dimensions are
specified in points (1 point is 1/72 inches). The UnitsConverter class can
be used to convert dimensions from pixels to points and from points to pixels.
You can specify the virtual display width and height in pixels using the PdfConverter.PageWidth
and PdfConverter.PageHeight properties or you can specify the same values
as parameters when you construct the PdfConverter object.
For the PDF Creator you can specify the virtual display width and height by setting
the the HtmlViewerWidth and HtmlViewerHeight properties of the
HtmlToPdfElement.
By default the PageWidth is set to 1024 pixels which should be sufficient to display
the majority of the web pages. If the web page you are converting cannot be completely
displayed in this width then you can increase this value or you can set the PageWidth
to 0 to allow the converter to automatically determine your web page width from
the HTML elements width. The PageHeight property is 0 by default which means the
virtual display height will be automatically set to display the whole HTML page
height. In general the PageHeight property should not be set in your code. However,
there are situations when the converter cannot automatically determine the web page
height for example when the web page contains a frame set because in this case the
web page can be displayed in any height. In such a situation you can manually set
the PageHeight to the desired value in pixels.
HTML Content Resizing in PDF Page
After the HTML content is displayed in the virtual display the virtual display content
will be transferred into PDF as you would take a picture of the virtual display
and put that picture into a PDF document. The PDF documents pages have a fixed size
in points. For example, the A4 portrait page is 595 points in width and 842 points
in height. If the virtual display width is more than 595 points then the rendered
HTML content would be shrunk to fit the PDF page width and display the whole HTML
content in the PDF document. If the virtual display width is less than 595 points
then the rendered HTML content will not be resized and will be rendered in the top
left corner of the PDF page at real size.
The dimension of the A4 portrait page in virtual device pixels is 793x1122 pixels.
This means that at a default virtual display width of 1024 pixels the HTML content
will be shrunk to fit the PDF page. This is the reason why you see smaller fonts
and images in PDF.
The calculation above does not take into account the possible margins set for the
PDF page and it is done at the default resoltion of 96 DPI. If you have set the
PDF page margins or if you are using a custom Windows DPI then the exact calculation
of the available width in PDF page can be made using UnitsConverter API.
The FitWidth property was added to the PdfConverter.PdfDocumentOptions to control
if the rendered HTML content can be scaled to fit the PDF page width. The default
value is true which makes the HTML content to be resized if necessary to fit the
PDF page width. When false, the HTML content will not be resized and it will be
rendered at the real size in PDF.
When the FitWidth property is false the HTML content could be wider than the PDF
page width and the therefore the HTML content will be cut off to the right in PDF.
In this case, in order to get the whole content in PDF you have to set a wider page
for the PDF document. You can first try to set landscape orientation for the PDF
page by setting PdfConverter.PdfDocumentOptions.PdfPageOrientation = PDFPageOrientation.Landscape.
If this not enough you can choose a wider standard page like A3 or A2. It is also
possible to set a custom size for the PDF page when the PdfConvert.PdfDocumentOptions.PdfPageSize=PdfPageSize.Custom
In this case the custom size of the PDF page will be taken from PdfConverter.PdfDocumentOptions.CustomPdfPageSize
property. The PdfConverter.PdfDocumentOptions.AutoSizePdfPage was added to automatically
determine a custom PDF page width when the FitWidth property is false. The AutoSizePdfPage
can create PDF documents with non-standard PDF page size.
If you don't want to resize the PDF page but you want to keep it A4 portrait for
example, then you have to decrease the virtual display width. If your page can be
correctly and entirely displayed in 793 pixels (which is the width of the A4 portrait
page in pixels without margins at default 96 dpi resolution) you can set this value
for PdfConverter.PageWidth property and you should get the whole HTML rendered at
real size in PDF.
The HTML content centering in PDF problem can be observed when the HTML content
size is fixed and it is less than 1024 pixels in width. In this case there will
normally be an empty space in the right side of the web page displayed at 1024 pixels.
When the virtual display content is transferred to PDF the content will appear as
not centered in PDF. You can also solve this if you set the PdfConverter.PageWidth
to a value of 793 pixels or less.
Single PDF Page Conversion
The HTML to PDF Converter offers the possibility to produce the whole HTML content
into a single PDF page automatically resized to display the whole content. To get
this behavior you have to set the PdfConverter.PdfDocumentOptions.SinglePage property
on true. When the FitWidth is true the PDF page width will be preserved, otherwise
the PDF page width will be automatically resized to display the whole HTML content.
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