'''' 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.TextImports GrapeCity.Documents.DrawingImports GrapeCity.Documents.Pdf.AnnotationsImports GCTEXT = GrapeCity.Documents.Text
'' This sample loads all images found in a directory, then renders each image'' in the largest possible size on a separate page of the PDF.'' Finally it inserts a TOC of image thumbnails linked to the large images'' into the document.'' See also SlidePages.Public Class ImageLinks    Private Class ImageInfo        Public Property Name As String        Public Property Image As IImage        Public Property PageIdx As Integer    End Class
    Function CreatePDF(ByVal stream As Stream) As Integer        Dim doc = New GcPdfDocument()        Dim fnt = GCTEXT.Font.FromFile(Path.Combine("Resources", "Fonts", "NotoSans-Bold.ttf"))        '' 1/4" page margins all around:        Const margin = 36.0F
        '' Load all images from the Resources/Images folder:        Dim imageInfos As New List(Of ImageInfo)        For Each fname In Directory.GetFiles(Path.Combine("Resources", "Images"), "*", SearchOption.AllDirectories)            imageInfos.Add(New ImageInfo() With {.Name = Path.GetFileName(fname), .Image = Util.ImageFromFile(fname)})        Next        imageInfos.Shuffle()        '' Set up image alignment that would center images horizontally and align to top vertically:        Dim ia = New ImageAlign(ImageAlignHorz.Center, ImageAlignVert.Top, True, True, True, False, False)        '' Image rectangle for full-sized images - whole page:        Dim rBig = New RectangleF(margin, margin, doc.PageSize.Width - margin * 2, doc.PageSize.Height - margin * 2)        '' Render all images full-size, one image per page:        For i = 0 To imageInfos.Count - 1            Dim g = doc.NewPage().Graphics            Dim ii = imageInfos(i)            g.DrawImage(ii.Image, rBig, Nothing, ia)            ii.PageIdx = i        Next        '' Insert page(s) with thumbnails into the beginning of the document as a 4x5 grid (see SlidePages):        Const rows = 5        Const cols = 4        Dim gapx = 72.0F / 4, gapy = gapx        Dim sWidth = (doc.PageSize.Width - margin * 2 + gapx) / cols        Dim sHeight = (doc.PageSize.Height - margin * 2 + gapy) / rows        If (sWidth > sHeight) Then            gapx += sWidth - sHeight            sWidth = sHeight        Else            gapy += sHeight - sWidth            sHeight = sWidth        End If        Const sMargin = 72.0F / 6        '' Center thumbnails vertically too:        ia.AlignVert = ImageAlignVert.Center        '' Text format for image captions:        Dim tf = New TextFormat() With {.Font = fnt, .FontSize = sMargin * 0.65F}        '' Insertion point:        Dim ip = New PointF(margin, margin)        Dim page = doc.Pages.Insert(0)        For i = 0 To imageInfos.Count() - 1            Dim ii = imageInfos(i)            Dim rect = New RectangleF(ip, New SizeF(sWidth - gapx, sHeight - gapy))            '' Add a link to the page where the full-sized image is (the page index            '' will be updated when we know how many pages are in TOC, see below):            page.Annotations.Add(New LinkAnnotation(rect, New DestinationFit(ii.PageIdx)))            '' Draw thumbnail:            Dim g = page.Graphics            g.FillRectangle(rect, Color.LightGray)            g.DrawRectangle(rect, Color.Black, 0.5F)            rect.Inflate(-sMargin, -sMargin)            Dim imageRect As RectangleF() = Nothing            g.DrawImage(ii.Image, rect, Nothing, ia, imageRect)            g.DrawRectangle(imageRect(0), Color.DarkGray, 1)            '' Print image file name as caption in the bottom slide margin:            g.DrawString(ii.Name, tf,                New RectangleF(rect.X, rect.Bottom, rect.Width, sMargin),                TextAlignment.Center, ParagraphAlignment.Near, False)            ip.X += sWidth            If (ip.X + sWidth > doc.PageSize.Width) Then                ip.X = margin                ip.Y += sHeight                If (ip.Y + sHeight > doc.PageSize.Height) Then                    page = doc.Pages.Insert(doc.Pages.IndexOf(page) + 1)                    ip.Y = margin                End If            End If        Next        '' We now go through all TOC pages, updating page indices in links' destinations        '' to account for the TOC pages inserted in the beginning of the document:        Dim tocPages = doc.Pages.IndexOf(page) + 1        For i = 0 To tocPages - 1            For Each ann In doc.Pages(i).Annotations                If TypeOf ann Is LinkAnnotation AndAlso TypeOf CType(ann, LinkAnnotation).Dest Is DestinationFit Then                    Dim link = DirectCast(ann, LinkAnnotation)                    Dim dest = DirectCast(CType(ann, LinkAnnotation).Dest, DestinationFit)                    link.Dest = New DestinationFit(dest.PageIndex.Value + tocPages)                End If            Next        Next        ''        '' Done:        doc.Save(stream)        imageInfos.ForEach(Sub(ii_) ii_.Image.Dispose())        Return doc.Pages.Count    End FunctionEnd Class