Chỉnh sửa PDF trong C# .NET

// Load the PDF file into Editor
Editor editor = new Editor("source.pdf");

// Create and adjust the PDF edit options
PdfEditOptions editOptions = new PdfEditOptions();

// Open input PDF document for edit — obtain an intermediate document, that can be edited
EditableDocument beforeEdit = editor.Edit(editOptions);

// Grab PDF document content and associated resources from editable document
string content = beforeEdit.GetEmbeddedHtml();

// Send the content to WYSIWYG-editor, edit it there, and send edited content back to the server-side
// This step simulates a such operation
string updatedContent = content.Replace("candy", "Edited candy");

// Grab edited content and resources from WYSIWYG-editor and create a new EditableDocument instance from it
EditableDocument afterEdit = EditableDocument.FromMarkup(updatedContent, null);

// Create a PDF save options        
PdfSaveOptions saveOptions = new PdfSaveOptions();

// Save edited PDF document to the file
editor.Save(afterEdit, outputPath, saveOptions);