Pagination is computed by a UI-independent engine (unvell.ReoGrid.Core.Printing) shared by PDF, WinForms, and WPF. Every output target produces the same result.

Page setup

using unvell.ReoGrid.Core.Printing;

ws.PrintSettings = new PrintSettings
{
	Paper = PaperKind.A4,
	Orientation = PageOrientation.Portrait,
	MarginLeft = 54,          // points (72 pt = 1 inch)
	MarginRight = 54,
	MarginTop = 54,
	MarginBottom = 54,
	PrintArea = RangePosition.Parse("A1:H60"),
	Scale = 1.0,
	CenterHorizontally = true,
	Order = PageOrder.DownThenOver,
	ShowGridLines = true,
	ShowHeaders = false,
};

Paper sizes

PaperKind is one of A5 / A4 / A3 / B5 / B4 / Letter / Legal / Tabloid / Executive / Custom.

For Custom, specify CustomWidthPt / CustomHeightPt in points.

Scale and fit-to-page

ws.PrintSettings = new PrintSettings
{
	FitToPagesWide = 1,       // fit to one page wide
	FitToPagesTall = null,    // as many pages tall as it takes
};

bool fit = ws.PrintSettings.IsFitToPage;

Scale ranges from 10% to 400% (MinScale / MaxScale). If either FitToPagesWide or FitToPagesTall is set, it takes precedence over Scale.

The on-screen zoom factor (control.Zoom) has no effect on printing.

Pagination rules

• Rows and columns are never split. Just like Excel, a row that does not fit is pushed to the next page
• Hidden rows and columns are treated as zero width/height
• PageOrder is the order in which pages are emitted (DownThenOver = down first, OverThenDown = across first)

Getting the page count up front

// when you only need the page count (no rendering involved)
PrintLayout layout = Paginator.Paginate(ws, ws.PrintSettings);
Console.WriteLine($"{layout.Pages.Count}  pages");

Since no rendering is involved, this works for preview UIs and batch processing.

Calls per output target

The WinForms version returns a PrintDocument, so you can pass it straight to the standard print dialog or print preview.

Print titles (repeated rows and columns)

Repeat the heading rows at the top of every page (Excel’s “print titles”).

// Repeat rows 1-2 at the top of every page, and column A down the left.
ws.PrintSettings.RepeatRows = new LineSpan(0, 1);
ws.PrintSettings.RepeatColumns = new LineSpan(0, 0);

LineSpan is an inclusive, 0-based band (new LineSpan(0, 1) = rows 1-2).

A repeated row or column is left out of the body, so it never prints twice on the same page. A span that would cover the whole print range is ignored — pages of nothing but titles help no one.

Header and footer

var hf = ws.PrintSettings.HeaderFooter;
hf.Header.Center = "&A";                 // sheet name
hf.Footer.Right = "&P / &N";             // 2 / 5
hf.Footer.Left = "&D &T";                // date and time
hf.FontSizePt = 9;

// A different banner on page 1 only.
hf.DifferentFirst = true;
hf.FirstHeader.Center = "Quarterly report";

// Distance from the paper edge to each band, in points.
ws.PrintSettings.MarginHeader = 21.6;
ws.PrintSettings.MarginFooter = 21.6;

Each band has a left, centre and right section and uses Excel’s format codes.

Codes that style part of a band — &B, &I, &14, &"font,style" — are not drawn, because a band is rendered in one style (FontSizePt). They are kept in the stored string, so a header authored in Excel round-trips intact.

&F expands only when a file name is supplied (PdfExporter.Export(..., documentName: path), or GridPrintDocument.DocumentFileName). An unsaved workbook leaves it empty rather than printing an invented name.

Persistence

PrintSettings round-trips through both XLSX (<pageSetup>, <headerFooter> and the built-in name _xlnm.Print_Titles) and reogrid-json (the print block). Opening the file in Excel gives you the same paper, orientation, margins, repeated rows and bands.

Not supported

• Printing only specific pages within the print area
• Manual page breaks (rowBreaks / colBreaks)
• Drawing the header/footer styling codes (&B and friends). They are preserved in the file.

Freeze panes are a screen-display feature and have no effect on printing (Freeze Panes).

What to read next

• PDF Export
• WinForms