261104: Created UG documentation for decrypting encrypted PDF files.

Security/Decrypting-encrypted-PDF-document/.NET/Decrypting-encrypted-PDF-document.sln

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+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.14.36408.4 d17.14
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Decrypting-encrypted-PDF-document", "Decrypting-encrypted-PDF-document\Decrypting-encrypted-PDF-document.csproj", "{93EFCE7C-2111-4150-AB8D-5E675DADB782}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{93EFCE7C-2111-4150-AB8D-5E675DADB782}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{93EFCE7C-2111-4150-AB8D-5E675DADB782}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{93EFCE7C-2111-4150-AB8D-5E675DADB782}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{93EFCE7C-2111-4150-AB8D-5E675DADB782}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {ACAC9DFE-C228-4D63-BEB8-B3F16EDEA60F}
+	EndGlobalSection
+EndGlobal

Security/Decrypting-encrypted-PDF-document/.NET/Decrypting-encrypted-PDF-document/Decrypting-encrypted-PDF-document.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <RootNamespace>Decrypting_encrypted_PDF_document</RootNamespace>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Syncfusion.Pdf.Net.Core" Version="*" />
+  </ItemGroup>
+
+</Project>

Security/Decrypting-encrypted-PDF-document/.NET/Decrypting-encrypted-PDF-document/Program.cs

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+using Syncfusion.Drawing;
+using Syncfusion.Pdf;
+using Syncfusion.Pdf.Graphics;
+using Syncfusion.Pdf.Parsing;
+using Syncfusion.Pdf.Security;
+
+using (FileStream inputStream = new FileStream(Path.GetFullPath(@"Data/Input.pdf"), FileMode.Open, FileAccess.Read))
+{
+    // Load the encrypted PDF document from the input stream
+    PdfLoadedDocument loadedDocument = new PdfLoadedDocument(inputStream, "syncfusion");
+
+    // Set the document permissions to default (removes any restrictions)
+    loadedDocument.Security.Permissions = PdfPermissionsFlags.Default;
+
+    // Clear the owner and user passwords to decrypt the document
+    loadedDocument.Security.OwnerPassword = string.Empty;
+    loadedDocument.Security.UserPassword = string.Empty;
+
+    using (FileStream outputStream = new FileStream(Path.GetFullPath(@"Output/Output.pdf"), FileMode.Create, FileAccess.Write))
+    {
+        // Save the decrypted PDF document to the output stream
+        loadedDocument.Save(outputStream);
+    }
+    // Close the loaded PDF document and release resources
+    loadedDocument.Close(true);
+}