In iTextSharp, can we set the vertical position of the pdfwriter?

I've recently started using iTextSharp to generate PDF reports from data. It works quite nicely.

In one particular report, I need a section to always appear at the bottom of the page. I'm using the PdfContentByte to create a dashed line 200f from the bottom:

cb.MoveTo(0f, 200f);
cb.SetLineDash(8, 4, 0);
cb.LineTo(doc.PageSize.Width, 200f);
cb.Stroke();

Now I'd like to insert content below that line. However, (as expected) the PdfContentByte metho开发者_高级运维ds don't change the vertical position of the PdfWriter. New paragraphs, for example, appear earlier in the page.

// appears wherever my last content was, NOT below the dashed line
doc.Add(new Paragraph("test", _myFont));

Is there some way to instruct the pdfwriter that I'd like to advance the vertical position to below the dashed line now, and continue inserting content there? There is a GetVerticalPosition() method -- it'd be nice if there was a corresponding Setter :-).

// Gives me the vertical position, but I can't change it
var pos = writer.GetVerticalPosition(false);

So, is there any way to set the writer's position by hand? Thanks!

Alright, I guess the answer is a bit obvious, but I was looking for a specific method. There's no setter for the vertical position, but you can easily just use a combination of writer.GetVerticalPosition() and paragraph.SpacingBefore to achieve this result.

My solution:

cb.MoveTo(0f, 225f);
cb.SetLineDash(8, 4, 0);
cb.LineTo(doc.PageSize.Width, 225f);
cb.Stroke();

var pos = writer.GetVerticalPosition(false);

var p = new Paragraph("test", _myFont) { SpacingBefore = pos - 225f };
doc.add(p);

Aside from SpacingBefore, the usual way to do it is by adding the text using the PdfContentByte instead of directly to the Document

// we create a writer that listens to the document
// and directs a PDF-stream to a file
PdfWriter writer = PdfWriter.getInstance(document, new FileStream("Chap1002.pdf", FileMode.Create));
document.Open();

// we grab the ContentByte and do some stuff with it
PdfContentByte cb = writer.DirectContent;

// we tell the ContentByte we're ready to draw text
cb.beginText();

// we draw some text on a certain position
cb.setTextMatrix(100, 400);
cb.showText("Text at position 100,400.");

// we tell the contentByte, we've finished drawing text
cb.endText();