Replace the existing image on the PDF file in C#/VB.NET

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To err is human and when it comes to documentation, we all can make mistakes. Modern day documents are mostly shared in the PDF format and contain lots of visuals and images. However, there will be times when you may wish to replace an image in the PDF document due to an error pasting the image or otherwise. In this article, I will take a detailed look at the methods for replacing the existing image on the PDF file. To achieve this functionality, you just need to follow a few simple steps. Read on for more information.

 

Programming Environment 

In this test, Free Spire.PDF for .NET is introduced into the program. The Spire.PDF.dll file can be referenced by:

 

Method 1: Download Free Spire.PDF for .NET locally, unzip it, and install it. After the installation is complete, find Spire.PDF.dll in the BIN folder under the installation path. Then open the "Solution Explorer" in Visual Studio, right-click "References", "Add Reference", and add a reference to the dll file in the BIN folder of the local path to the program.

 

Method 2: Install via NuGet. It can be installed by the following 2 methods:

 

(1) You can open the "Solution Explorer" in Visual Studio, right-click "References", "Manage NuGet Packages", then search for "Free Spire.PDF", and click "Install". Wait for the program installation to complete.

 

(2) Copy the following content to the PM console installation.

 

Install-Package FreeSpire.PDF -Version 8.6.0

 


Replace the existing image

  • Create a new instance of PdfDocument and load a PDF document from file using PdfDocument.LoadFromFile() method.
  • Get the first page of the loaded PDF file.
  • Load the new image that we want to replace the existing image.
  • Replace first image on the PDF file with the new loaded image using page.ReplaceImage()method.
  • Save the document to file using PdfDocument.SaveToFile() method.

The following code sample shows how to add text watermarks to PDF. 

【C#】

using Spire.Pdf;

using Spire.Pdf.Graphics;

 

namespace ReplaceImage

{

    class Program

    {

        static void Main(string[] args)

        {

            // Create a new instance of PdfDocument and load a PDF document from file

            PdfDocument doc = new PdfDocument();

            doc.LoadFromFile("Yellowstone National Park.pdf");

 

            //Get the first page of the loaded PDF file

            PdfPageBase page = doc.Pages[0];

 

            // Load the new image that we want to replace the existing image

            PdfImage image = PdfImage.FromFile("image.jpg");

 

            //Replace first image on the PDF file with the new loaded image

            page.ReplaceImage(0, image);

 

            //Save the document to file

            doc.SaveToFile("result.pdf");

        }

    }


【VB.NET】

Imports Spire.Pdf

Imports Spire.Pdf.Graphics

 

Namespace ReplaceImage

    Friend Class Program

        Private Shared Sub Main(ByVal args As String())

            ' Create a new instance of PdfDocument and load a PDF document from file

            Dim doc As PdfDocument = New PdfDocument()

            doc.LoadFromFile("Yellowstone National Park.pdf")

 

            'Get the first page of the loaded PDF file

            Dim page As PdfPageBase = doc.Pages(0)

 

            ' Load the new image that we want to replace the existing image

            Dim image As PdfImage = PdfImage.FromFile("image.jpg")

 

            'Replace first image on the PDF file with the new loaded image

            page.ReplaceImage(0, image)

 

            'Save the document to file

            doc.SaveToFile("result.pdf")

        End Sub

    End Class

End Namespace

 

Effective shot:


Attention:

The code path is for reference only, and you can customize the path as you want.

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