How to: Create Graphics in a Document with Landscape and Portrait Page Orientations

• Jun 10, 2019
• 3 minutes to read

Important

You require a license to the DevExpress Office File API or DevExpress Universal Subscription to use these examples in production code. Refer to the DevExpress Subscription page for pricing information.

This example shows how to add text to the top left and bottom right of a page in a document with landscape and portrait pages.

PDF graphics are represented by an instance of the PdfGraphics class. To create graphics, call the PdfDocumentProcessor.CreateGraphics method. To access PdfGraphics, you need to reference the DevExpress.Pdf.Drawing assembly.

To rotate text that should be drawn in a document with landscape and portrait pages, call the PdfGraphics.RotateTransform method.

To move rotated text to desired position (bottom right) on a page, call the PdfGraphics.TranslateTransform method.

To draw text on a page, call the PdfGraphics.DrawString method with the specified text, font, brush and location.

To add graphics to a page foreground, call the PdfGraphics.AddToPageForeground method.

Note

A complete sample project is available at https://github.com/DevExpress-Examples/how-to-create-graphics-in-a-document-with-landscape-and-portrait-page-orientations-t383767

Program.cs

using System.Drawing;
using System.Collections.Generic;
using DevExpress.Pdf;

namespace CreateGraphics {
    class Program {
        const float DrawingDpi = 72f;

        static void Main(string[] args) {
            using (PdfDocumentProcessor processor = new PdfDocumentProcessor()) {
                processor.LoadDocument("..\\..\\RotatedDocument.pdf");
                using (SolidBrush textBrush = new SolidBrush(Color.FromArgb(100, Color.Blue)))
                    AddGraphics(processor, "text", textBrush);
                processor.SaveDocument("..\\..\\RotatedDocumentWithGraphics.pdf");
            }
        }

        static void AddGraphics(PdfDocumentProcessor processor, string text, SolidBrush textBrush) {
            IList<PdfPage> pages = processor.Document.Pages;
            for (int i = 0; i < pages.Count; i++) {
                PdfPage page = pages[i];
                using (PdfGraphics graphics = processor.CreateGraphics()) {
                    SizeF actualPageSize = PrepareGraphics(page, graphics);
                    using (Font font = new Font("Segoe UI", 20, FontStyle.Regular)) {
                        SizeF textSize = graphics.MeasureString(text, font, PdfStringFormat.GenericDefault);
                        PointF topLeft = new PointF(0, 0);
                        PointF bottomRight = new PointF(actualPageSize.Width - textSize.Width, actualPageSize.Height - textSize.Height);
                        graphics.DrawString(text, font, textBrush, topLeft);
                        graphics.DrawString(text, font, textBrush, bottomRight);
                        graphics.AddToPageForeground(page, DrawingDpi, DrawingDpi);
                    }
                }
            }
        }

        static SizeF PrepareGraphics(PdfPage page, PdfGraphics graphics) {
            PdfRectangle cropBox = page.CropBox;
            float cropBoxWidth = (float)cropBox.Width;
            float cropBoxHeight = (float)cropBox.Height;

            switch (page.Rotate) {
                case 90:
                    graphics.RotateTransform(-90);
                    graphics.TranslateTransform(-cropBoxHeight, 0);
                    return new SizeF(cropBoxHeight, cropBoxWidth);
                case 180:
                    graphics.RotateTransform(-180);
                    graphics.TranslateTransform(-cropBoxWidth, -cropBoxHeight);
                    return new SizeF(cropBoxWidth, cropBoxHeight);
                case 270:
                    graphics.RotateTransform(-270);
                    graphics.TranslateTransform(0, -cropBoxWidth);
                    return new SizeF(cropBoxHeight, cropBoxWidth);
            }
            return new SizeF(cropBoxWidth, cropBoxHeight);
        }
    }
}

Program.vb

Imports System.Drawing
Imports System.Collections.Generic
Imports DevExpress.Pdf

Namespace CreateGraphics
    Friend Class Program
        Private Const DrawingDpi As Single = 72F

        Shared Sub Main(ByVal args() As String)
            Using processor As New PdfDocumentProcessor()
                processor.LoadDocument("..\..\RotatedDocument.pdf")
                Using textBrush As New SolidBrush(Color.FromArgb(100, Color.Blue))
                    AddGraphics(processor, "text", textBrush)
                End Using
                processor.SaveDocument("..\..\RotatedDocumentWithGraphics.pdf")
            End Using
        End Sub

        Private Shared Sub AddGraphics(ByVal processor As PdfDocumentProcessor, ByVal text As String, ByVal textBrush As SolidBrush)
            Dim pages As IList(Of PdfPage) = processor.Document.Pages
            For i As Integer = 0 To pages.Count - 1
                Dim page As PdfPage = pages(i)
                Using graphics As PdfGraphics = processor.CreateGraphics()
                    Dim actualPageSize As SizeF = PrepareGraphics(page, graphics)
                    Using font As New Font("Segoe UI", 20, FontStyle.Regular)
                        Dim textSize As SizeF = graphics.MeasureString(text, font, PdfStringFormat.GenericDefault)
                        Dim topLeft As New PointF(0, 0)
                        Dim bottomRight As New PointF(actualPageSize.Width - textSize.Width, actualPageSize.Height - textSize.Height)
                        graphics.DrawString(text, font, textBrush, topLeft)
                        graphics.DrawString(text, font, textBrush, bottomRight)
                        graphics.AddToPageForeground(page, DrawingDpi, DrawingDpi)
                    End Using
                End Using
            Next i
        End Sub

        Private Shared Function PrepareGraphics(ByVal page As PdfPage, ByVal graphics As PdfGraphics) As SizeF
            Dim cropBox As PdfRectangle = page.CropBox
            Dim cropBoxWidth As Single = CSng(cropBox.Width)
            Dim cropBoxHeight As Single = CSng(cropBox.Height)

            Select Case page.Rotate
                Case 90
                    graphics.RotateTransform(-90)
                    graphics.TranslateTransform(-cropBoxHeight, 0)
                    Return New SizeF(cropBoxHeight, cropBoxWidth)
                Case 180
                    graphics.RotateTransform(-180)
                    graphics.TranslateTransform(-cropBoxWidth, -cropBoxHeight)
                    Return New SizeF(cropBoxWidth, cropBoxHeight)
                Case 270
                    graphics.RotateTransform(-270)
                    graphics.TranslateTransform(0, -cropBoxWidth)
                    Return New SizeF(cropBoxHeight, cropBoxWidth)
            End Select
            Return New SizeF(cropBoxWidth, cropBoxHeight)
        End Function
    End Class
End Namespace