Lock PDF via C#

Encrypt PDF files. Use Aspose.PDF for .NET to modify PDF documents programmatically

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Protect PDF Document Using C#

Lock PDF using Aspose.PDF .NET. Locking PDF with passwords or encryption is essential for keeping sensitive content confidential and stopping unauthorized access to data. When you lock PDF with password, it gains control over who can access its content, allowing you to set permissions for reading, editing, or printing. Lock PDF prevents unauthorized changes to the document, maintaining its accuracy and reliability. This is especially important for protecting personal or confidential info and ensuring the safety of user identities and their privacy. Lock PDF with password files helps protect your personal info. Often some industries have strict rules about safeguarding confidential information. Locking PDF can fulfill these requirements and provide the necessary protection. It’s crucial to use encryption responsibly, following the law and ethical guidelines. Always make sure you have the right permissions to secure documents properly. Locking a PDF is vital for safeguarding the privacy and security of the data it holds, especially when keeping information safe is a top priority. In order to encrypt PDF file, we’ll use Aspose.PDF for .NET API which is a feature-rich, powerful and easy to use document manipulation API for net platform. Open NuGet package manager, search for Aspose.PDF and install. You may also use the following command from the Package Manager Console.

Package Manager Console

PM > Install-Package Aspose.PDF

How to Protect PDF - C#

You need Aspose.PDF for .NET to try the code in your environment.

  1. Open a PDF document using Document object.
  2. Create a password for user and owner.
  3. Call Document.Encrypt Method.
  4. Save the PDF file.

The provided C# code snippet shows how to lock PDF documents using the Aspose.PDF library. It opens a PDF document named ‘Encrypt.pdf’. It encrypts the opened PDF using encryption settings. The user password and owner password are provided for accessing and managing permissions, and it uses the RC4x128 encryption algorithm. The ‘0’ signifies that no specific permissions are granted for users to modify the document. After encrypting the PDF, the code saves the updated document to a file named ‘Encrypt_out.pdf’ in the same directory specified by the ‘dataDir’ variable. This code snippet is a simplified example of how you might use a Aspose.PDF library or framework to lock PDF file and save the locked version.

Lock PDF Document - C#

This sample code shows how to encrypt PDF file - C#

Input file:

File not added

Password:

Output format:

Output file:

    // Open document
    Document document = new Document(dataDir+ "Encrypt.pdf");
    // Encrypt PDF
    document.Encrypt("user", "owner", 0, CryptoAlgorithm.RC4x128);
    dataDir = dataDir + "Encrypt_out.pdf";
    // Save updated PDF
    document.Save(dataDir);