string text = File.ReadAllText(@"..\texttopdf.txt");

Dim text As String = File.ReadAllText("..\texttopdf.txt")

  PdfPageBase page = section.Pages.Add();
            PdfFont font = new PdfFont(PdfFontFamily.Helvetica, 11);
            PdfStringFormat format = new PdfStringFormat();
            format.LineSpacing = 20f;
            float pageWidth = page.Canvas.ClientSize.Width;
            PdfBrush brush = PdfBrushes.DarkBlue;
            float y = 30;
            PdfStringLayouter textLayouter = new PdfStringLayouter();
            PdfStringLayoutResult result
                = textLayouter.Layout(text, font, format, new SizeF(pageWidth, 0));
            foreach (LineInfo line in result.Lines)
            {
                page.Canvas.DrawString(line.Text, font, brush, 0, y, format);
                y = y + result.LineHeight;
            }

Dim page As PdfPageBase = section.Pages.Add()
	Dim font As New PdfFont(PdfFontFamily.Helvetica, 11)
	Dim format As New PdfStringFormat()
	format.LineSpacing = 20F
	Dim pageWidth As Single = page.Canvas.ClientSize.Width
	Dim brush As PdfBrush = PdfBrushes.DarkBlue
	Dim y As Single = 30
	Dim textLayouter As New PdfStringLayouter()
	Dim result As PdfStringLayoutResult = textLayouter.Layout(text, font, format, New SizeF(pageWidth, 0))

	For Each line As LineInfo In result.Lines
		page.Canvas.DrawString(line.Text, font, brush, 0, y, format)
		y = y + result.LineHeight
	Next

doc.LoadFromFile(@"..\Sample.pdf");
System.Drawing.Image image = System.Drawing.Image.FromFile(@"..\MS.jpg");

doc.LoadFromFile("..\Sample.pdf")
Dim image As System.Drawing.Image = System.Drawing.Image.FromFile("..\MS.jpg")

//adjust image size
int width = image.Width;
int height = image.Height;
float schale = 0.7f;
System.Drawing.Size size = new System.Drawing.Size((int)(width * schale), (int)(height * schale));
Bitmap schaleImage = new Bitmap(image, size);
//draw image into the first PDF page at specific position 
PdfImage pdfImage = PdfImage.FromImage(schaleImage);
PdfPageBase page0 = doc.Pages[0];
PointF position = new PointF((page0.Canvas.ClientSize.Width - schaleImage.Width) / 8, 10);
page0.Canvas.DrawImage(pdfImage, position);

'adjust image size
Dim width As Integer = image.Width
Dim height As Integer = image.Height
Dim schale As Single = 0.7F
Dim size As New System.Drawing.Size(CInt(Math.Truncate(width * schale)), CInt(Math.Truncate(height * schale)))
Dim schaleImage As New Bitmap(image, size)
'draw image into the first PDF page at specific position 
Dim pdfImage__1 As PdfImage = PdfImage.FromImage(schaleImage)
Dim page0 As PdfPageBase = doc.Pages(0)
Dim position As New PointF((page0.Canvas.ClientSize.Width - schaleImage.Width) / 8, 10)
page0.Canvas.DrawImage(pdfImage__1, position)

            //pdf document list
            String[] files = new String[]
            {
                @"D:\e-iceblue\Spire.PDF\Demos\Data\DigitalSignature.pdf",
                @"D:\e-iceblue\Spire.PDF\Demos\Data\Sample2.pdf",
                @"D:\e-iceblue\Spire.PDF\Demos\Data\ImageWaterMark.pdf"                            
            };

'pdf document list
Dim files As [String]() = New [String]() {"D:\e-iceblue\Spire.PDF\Demos\Data\DigitalSignature.pdf", "D:\e-iceblue\Spire.PDF\Demos\Data\Sample2.pdf", "D:\e-iceblue\Spire.PDF\Demos\Data\ImageWaterMark.pdf"}
          

           //open pdf documents            
            PdfDocument[] docs = new PdfDocument[files.Length];
            for (int i = 0; i < files.Length; i++)
            {
                docs[i] = new PdfDocument(files[i]);
            }
            //append document
            docs[0].AppendPage(docs[1]);
            //import pages
            for (int i = 0; i < docs[2].Pages.Count; i = i + 2)
            {
                docs[0].InsertPage(docs[2], i);
            }

	'open pdf documents            
	Dim docs As PdfDocument() = New PdfDocument(files.Length - 1) {}
	For i As Integer = 0 To files.Length - 1
		docs(i) = New PdfDocument(files(i))
	Next
	'append document
	docs(0).AppendPage(docs(1))
	'import pages
	Dim i As Integer = 0
	While i < docs(2).Pages.Count
		docs(0).InsertPage(docs(2), i)
		i = i + 2
	End While
          

            docs[0].SaveToFile("MergeDocuments.pdf");
            foreach (PdfDocument doc in docs)
            {
                doc.Close();
            }
            PDFDocumentViewer("MergeDocuments.pdf");

docs(0).SaveToFile("MergeDocuments.pdf")
For Each doc As PdfDocument In docs
	doc.Close()
Next
PDFDocumentViewer("MergeDocuments.pdf")

String pfxPath = @"..\Data\Demo.pfx";
PdfCertificate cert = new PdfCertificate(pfxPath, "e-iceblue");
PdfSignature signature = new PdfSignature(doc, page, cert, "demo");
signature.ContactInfo = "Harry Hu";
signature.Certificated = true;
signature.DocumentPermissions = PdfCertificationFlags.AllowFormFill;

Dim pfxPath As String = "..\Data\Demo.pfx"
Dim cert As New PdfCertificate(pfxPath, "e-iceblue")
Dim signature As New PdfSignature(doc, page, cert, "demo")
signature.ContactInfo = "Harry Hu"
signature.Certificated = True
signature.DocumentPermissions = PdfCertificationFlags.AllowFormFill