How to rotate an image around its center in PDF document using C#?
The Syncfusion Essential® PDF is a feature-rich and high-performance .NET PDF library that is used to create, read, and edit PDF documents programmatically without Adobe dependencies. This library also offers functionality to merge, split, stamp, forms, compress, and secure PDF files. Using this library, you can rotate an image around its center in a pdf document.
Steps to rotate an image around its center in the pdf document programmatically
1. Create a new C# console application project.
2. Install the Syncfusion.PDF.WinForms NuGet packages as a reference to your .NET Framework application from the NuGet.org.
3. Include the following namespaces in the Program.cs file.
C#
using Syncfusion.Pdf; using Syncfusion.Pdf.Graphics;
VB.NET
Imports Syncfusion.Pdf Imports Syncfusion.Pdf.Graphics
4. The following code example shows how to rotate an image around its center in the pdf document using C#.
C#
//Create a document
PdfDocument doc = new PdfDocument();
string[] files = Directory.GetFiles(Path.Combine("../../Images/"));
//Add a new page
PdfPage page = doc.Pages.Add();
int rotationAngle = 270;
float x = 40, y = 400;
for (int i = 0; i < files.Length; i++)
{
//Load an image
PdfBitmap image = new PdfBitmap(files[i]);
DrawRotateImage(page, image, rotationAngle, x, y);
//provide the angle and x and y position based on your requirement.
rotationAngle += 40;
x += 300;
y += 100;
}
string outputFileName = rotationAngle.ToString() + ".pdf";
//Save the PDF
doc.Save(outputFileName);
//Close the PDF
doc.Close(true);
/// <summary>
/// Calculate the translate transform
/// </summary>
private static void DrawRotateImage(PdfPage page, PdfBitmap image, int rotationAngle, float x, float y)
{
//Save the current graphics state
PdfGraphicsState state = page.Graphics.Save();
page.Graphics.TranslateTransform(x, y);
//Translate the coordinate system to the center of image
page.Graphics.TranslateTransform(image.GetBounds().Width / 2, image.GetBounds().Height / 2);
//Rotate the coordinate system
page.Graphics.RotateTransform(-rotationAngle);
page.Graphics.TranslateTransform(-image.GetBounds().Width / 2, -image.GetBounds().Height / 2);
// Draw an image
page.Graphics.DrawImage(image, 0, 0);
//Restore the graphics state
page.Graphics.Restore(state);
}
VB.NET
'Create a document
Dim doc As PdfDocument = New PdfDocument()
Dim files As String() = Directory.GetFiles(Path.Combine("../../Images/"))
'Add a new page
Dim page As PdfPage = doc.Pages.Add()
Dim rotationAngle As Integer = 270
Dim x As Single = 40, y As Single = 400
For i As Integer = 0 To files.Length - 1
'Load an image
Dim image As PdfBitmap = New PdfBitmap(files(i))
DrawRotateImage(page, image, rotationAngle, x, y)
'provide the angle and x and y position based on your requirement.
rotationAngle += 40
x += 300
y += 100
Next
Dim outputFileName As String = rotationAngle.ToString() & ".pdf"
'Save the PDF
doc.Save(outputFileName)
'Close the PDF
doc.Close(True)
'Calculate the translate transform
Private Shared Sub DrawRotateImage(ByVal page As PdfPage, ByVal image As PdfBitmap, ByVal rotationAngle As Integer, ByVal x As Single, ByVal y As Single)
'Save the current graphics state
Dim state As PdfGraphicsState = page.Graphics.Save()
page.Graphics.TranslateTransform(x, y)
'Translate the coordinate system to the center of image
page.Graphics.TranslateTransform(image.GetBounds().Width / 2, image.GetBounds().Height / 2)
'Rotate the coordinate system
page.Graphics.RotateTransform(-rotationAngle)
page.Graphics.TranslateTransform(-image.GetBounds().Width / 2, -image.GetBounds().Height / 2)
'Draw an image
page.Graphics.DrawImage(image, 0, 0)
'Restore the graphics state
page.Graphics.Restore(state)
End Sub
A complete working sample can be downloaded from the rotate image in all positions in the pdf document sample.
By executing the program, you will get the PDF document as follows.
Refer here to explore the rich set of Syncfusion Essential® PDF features.
Starting with v16.2.0.x, if you reference Syncfusion® assemblies from the trial setup or the NuGet feed, include a license key in your projects. Refer to the link to learn about generating and registering the Syncfusion® license key in your application to use the components without trail message.
See Also:
https://support.syncfusion.com/kb/article/8533/how-to-rotate-images-in-a-pdf-using-c-and-vb-net
https://help.syncfusion.com/file-formats/pdf/working-with-images
https://support.syncfusion.com/kb/article/8684/how-to-avoid-auto-rotation-of-images-in-pdf-using-c-and-vb-net
https://support.syncfusion.com/kb/article/8067/how-to-rotate-pages-in-winforms-pdf-file
https://support.syncfusion.com/kb/article/8575/how-to-rotate-a-pdf-document-based-on-angle-using-c-and-vb-net
Conclusion
I hope you enjoyed learning about how to rotate an image around its centre in PDF document using C#.
You can refer to our WinForms PDF feature tour page to know about its other groundbreaking feature representations and documentation, and how to quickly get started for configuration specifications. You can also explore our WinForms PDF example to understand how to create and manipulate data.
For current customers, you can check out our components from the License and Downloads page. If you are new to Syncfusion®, you can try our 30-day free trial to check out our other controls.
If you have any queries or require clarifications, please let us know in the comments section below. You can also contact us through our support forums, Direct-Trac, or feedback portal. We are always happy to assist you!
