PDF加密和解密

import {PdfDocument} from "@ironsoftware/ironpdf";

(async () => {
    // Import a PDF document or create a new PDF from Html
    const pdf = await PdfDocument.open("encrypted.pdf", "password");
    
    // Create an empty Map
    const newMetadata = new Map();

    // Add key-value pairs of metadata
    newMetadata.set("Author", "Satoshi Nakamoto");
    newMetadata.set("Keywords", "SEO, Friendly");

    await pdf.overrideMetadata(newMetadata);

    await pdf.removePasswordsAndEncryption();
    // Make PDF read-only
    await pdf.makePdfDocumentReadOnly("secret-key");

    // Configure permissions
    const permissions = {
        AllowAnnotations: false,
        AllowExtractContent: false,
        AllowFillForms: false,
        AllowPrint: true,
    };

    await pdf.setPermission(permissions);
    
    // Change or set the document encrpytion password
    await pdf.saveAs("secured.pdf", {userPassword:"my-password"});
})();

PDF加密和解密

本代码示例演示了如何使用 IronPDF 强大的 C# .NET PDF 库修改元数据、使 PDF 为只读、配置权限以及更改文档加密密码。

首先，使用打开方式导入现有的 PDF 文档。通过将密码指定为第二个参数，该方法可用于打开受密码保护的文档，从而为安全文件提供强大的处理能力。

要设置新的元数据信息，首先要创建一个字典，并为元数据添加键值对，如作者和关键字。利用 IronPDF 中的 overrideMetadata 方法将新的元数据有效地应用到 PDF 文档中。

接下来，使用 IronPDF 提供的 removePasswordsAndEncryption 方法移除密码和加密，并通过 makePdfDocumentReadOnly 方法设置新密码，将 PDF 配置为只读，确保文档的完整性和安全性。

PDF 文档的权限是通过名为 "权限 "的对象配置的，该对象指定是否允许或禁止某些操作，如注释、内容提取、表格填写和打印。将权限对象传递给 setPermission 方法，以精确控制文档的可访问性功能。

最后，将文档加密密码修改或设置为 "my-password"，并将修改后的 PDF 保存为 "secured.pdf"，展示 IronPDF 在应用程序开发中安全管理文档的能力。

// Import the necessary namespace.
using IronPdf;

class PdfExample
{
    static void Main()
    {
        // Open an existing PDF document. If the document is password protected, provide the password.
        var pdf = IronPdf.PdfDocument.FromFile("existing.pdf", "document-password");

        // Initialize a dictionary to store metadata key-value pairs.
        var newMetadata = new Dictionary<string, string>
        {
            { "Author", "New Author" },
            { "Keywords", "PDF, Documentation, Example" }
        };

        // Apply the new metadata to the PDF document.
        pdf.OverrideMetadata(newMetadata);

        // Remove any existing passwords and encryption.
        pdf.RemovePasswordsAndEncryption();

        // Make the PDF document read-only by setting a read-only password.
        pdf.MakePdfDocumentReadOnly("read-only-password");

        // Define and set the permissions for the PDF document.
        var permissions = new PdfPermissions
        {
            AllowAnnotations = false,
            AllowContentExtraction = false,
            AllowFormFilling = true,
            AllowPrinting = false,
            AllowDocumentAssembly = false
        };
        pdf.SetPermissions(permissions);

        // Change the document encryption password.
        pdf.SaveAs("secured.pdf", "my-password"); // Save the modified PDF with a new security password.
    }
}

// Import the necessary namespace.
using IronPdf;

class PdfExample
{
    static void Main()
    {
        // Open an existing PDF document. If the document is password protected, provide the password.
        var pdf = IronPdf.PdfDocument.FromFile("existing.pdf", "document-password");

        // Initialize a dictionary to store metadata key-value pairs.
        var newMetadata = new Dictionary<string, string>
        {
            { "Author", "New Author" },
            { "Keywords", "PDF, Documentation, Example" }
        };

        // Apply the new metadata to the PDF document.
        pdf.OverrideMetadata(newMetadata);

        // Remove any existing passwords and encryption.
        pdf.RemovePasswordsAndEncryption();

        // Make the PDF document read-only by setting a read-only password.
        pdf.MakePdfDocumentReadOnly("read-only-password");

        // Define and set the permissions for the PDF document.
        var permissions = new PdfPermissions
        {
            AllowAnnotations = false,
            AllowContentExtraction = false,
            AllowFormFilling = true,
            AllowPrinting = false,
            AllowDocumentAssembly = false
        };
        pdf.SetPermissions(permissions);

        // Change the document encryption password.
        pdf.SaveAs("secured.pdf", "my-password"); // Save the modified PDF with a new security password.
    }
}

' Import the necessary namespace.
Imports IronPdf

Friend Class PdfExample
	Shared Sub Main()
		' Open an existing PDF document. If the document is password protected, provide the password.
		Dim pdf = IronPdf.PdfDocument.FromFile("existing.pdf", "document-password")

		' Initialize a dictionary to store metadata key-value pairs.
		Dim newMetadata = New Dictionary(Of String, String) From {
			{"Author", "New Author"},
			{"Keywords", "PDF, Documentation, Example"}
		}

		' Apply the new metadata to the PDF document.
		pdf.OverrideMetadata(newMetadata)

		' Remove any existing passwords and encryption.
		pdf.RemovePasswordsAndEncryption()

		' Make the PDF document read-only by setting a read-only password.
		pdf.MakePdfDocumentReadOnly("read-only-password")

		' Define and set the permissions for the PDF document.
		Dim permissions = New PdfPermissions With {
			.AllowAnnotations = False,
			.AllowContentExtraction = False,
			.AllowFormFilling = True,
			.AllowPrinting = False,
			.AllowDocumentAssembly = False
		}
		pdf.SetPermissions(permissions)

		' Change the document encryption password.
		pdf.SaveAs("secured.pdf", "my-password") ' Save the modified PDF with a new security password.
	End Sub
End Class

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