'''' This code is part of Document Solutions for PDF .NET demos.'' Copyright (c) MESCIUS inc. All rights reserved.''Imports System.IOImports System.DrawingImports GrapeCity.Documents.PdfImports GrapeCity.Documents.Text
'' Demonstrates a simple way to generate left/centered/right aligned page headers and footers.Public Class PageHeaders
    '' The document being generated:    Private _doc As GcPdfDocument
    '' Utility method to draw a part of a page header or footer.    '' Parameters:    '' - text: The part's text.    '' - tf: The text format to use.    '' - pageIdx: The page index.    '' - header: True if this is a header, false if a footer.    '' - horzAlign: Horizontal alignment (left/center/right).    Private Sub RenderHeader(ByVal text As String, ByVal tf As TextFormat, ByVal pageIdx As Integer, ByVal header As Boolean, ByVal horzAlign As TextAlignment)        Dim page = _doc.Pages(pageIdx)        Dim tl = page.Graphics.CreateTextLayout()        tl.MaxWidth = page.Size.Width        tl.MaxHeight = page.Size.Height        '' 1" margins, adjust as needed:        tl.MarginLeft = 72        tl.MarginRight = 72        '' 1/3" spacing above top/below bottom header, adjust as needed:        tl.MarginTop = 72 / 3        tl.MarginBottom = tl.MarginTop        '' Vertical alignment:        tl.ParagraphAlignment = If(header, ParagraphAlignment.Near, ParagraphAlignment.Far)        '' Horizontal alignment:        tl.TextAlignment = horzAlign        tl.Append(text, tf)        '' NOTE: if some part of a header or footer is static, we could cache the corresponding TextLayout        '' object and save some cycles by just drawing that cached TextLayout on each page w/out anything else:        tl.PerformLayout(True)        '' Draw the header at (0,0) (header located by margins and alignment):        page.Graphics.DrawTextLayout(tl, PointF.Empty)    End Sub
    '' The main program.    Function CreatePDF(ByVal stream As Stream) As Integer        _doc = New GcPdfDocument()        Dim page = _doc.NewPage()        '' Add a note about flipping landscape:        Dim noteRect = Util.AddNote(                "We flip page orientation in this sample only to show that these page headers can adapt to the changing page size.",                page)        ''        '' Prepare a TextLayout with some long text and print it (see PaginatedText for details):        Dim tl = page.Graphics.CreateTextLayout()        tl.DefaultFormat.Font = StandardFonts.Times        tl.DefaultFormat.FontSize = 12        tl.MaxWidth = _doc.PageSize.Width        tl.MaxHeight = _doc.PageSize.Height        tl.MarginAll = tl.Resolution        tl.MarginTop = noteRect.Bottom + 18        '' Add sample text:        tl.Append(Util.LoremIpsum(20))        '' Calculate glyphs and perform layout (see also PerformLayout call in the loop below):        tl.PerformLayout(True)        '' In a loop, split and render the text:        While True            Dim rest As TextLayout = Nothing            Dim splitResult = tl.Split(Nothing, rest)            page.Graphics.DrawTextLayout(tl, PointF.Empty)            If splitResult <> SplitResult.Split Then                Exit While            End If            tl = rest            tl.MarginTop = tl.Resolution            page = _doc.Pages.Add()            '' For sample sake, toggle page orientation:            page.Landscape = Not _doc.Pages(_doc.Pages.Count - 2).Landscape            '' Update layout size to reflect the new page orientation:            tl.MaxWidth = page.Size.Width            tl.MaxHeight = page.Size.Height            '' Because we changed layout size, we must perform layout again -            '' but can do it without recalculating glyphs:            tl.PerformLayout(False)        End While        '' Render the headers in a separate loop (so that we can provide 'Page X of Y' header):        Dim tf = New TextFormat() With {.Font = StandardFonts.Helvetica, .FontSize = 10, .ForeColor = Color.Gray}        Dim now = Util.TimeNow().ToString("u")        For pageIdx = 0 To _doc.Pages.Count - 1            RenderHeader(now, tf, pageIdx, True, TextAlignment.Leading)            RenderHeader("Easy Page Headers Sample", tf, pageIdx, True, TextAlignment.Center)            RenderHeader($"Page {pageIdx + 1} of {_doc.Pages.Count}", tf, pageIdx, True, TextAlignment.Trailing)            RenderHeader("Page footer - left", tf, pageIdx, False, TextAlignment.Leading)            RenderHeader("DsPdf", tf, pageIdx, False, TextAlignment.Center)            RenderHeader("Page footer - right", tf, pageIdx, False, TextAlignment.Trailing)        Next        ''        '' Done:        _doc.Save(stream)        Return _doc.Pages.Count    End FunctionEnd Class