PDF Find & Replace SDK for .NET

using Exis.PdfEditor;
using Exis.PdfEditor.Licensing;

ExisLicense.Initialize();  // Free 14-day trial - no key needed

var result = PdfFindReplace.Execute(
    "contract.pdf",
    "contract-updated.pdf",
    "Acme Corporation",
    "Globex Industries");

Console.WriteLine($"Replaced {result.TotalReplacements} occurrences " +
                  $"across {result.PagesModified} pages.");

var pairs = new[]
{
    new FindReplacePair("2025", "2026"),
    new FindReplacePair("Draft", "Final"),
    new FindReplacePair("CONFIDENTIAL", "PUBLIC"),
};

var result = PdfFindReplace.Execute(
    "report.pdf",
    "report-final.pdf",
    pairs);

var options = new PdfFindReplaceOptions { UseRegex = true };

// Replace all US phone numbers with a placeholder
var result = PdfFindReplace.Execute(
    "document.pdf",
    "redacted.pdf",
    @"\(\d{3}\)\s?\d{3}-\d{4}",
    "[PHONE REDACTED]",
    options);

// Purchase at officefindreplace.com/Home/pdf-find-replace-csharp - $499/developer/year
ExisLicense.Initialize("XXXX-XXXX-XXXX-XXXX");

// Unlimited pages, no restrictions, no console messages
var result = PdfFindReplace.Execute("large-doc.pdf", "output.pdf", "old", "new");

var options = new PdfFindReplaceOptions
{
    CaseSensitive = true,
    WholeWordOnly = false,
    UseRegex = false,
    UseIncrementalUpdate = true,
    TextFitting = TextFittingMode.Adaptive,  // Best quality text fitting
    MinHorizontalScale = 70,                 // Minimum Tz percentage (50-100)
    MaxFontSizeReduction = 1.5               // Max font size reduction in points
};

var result = PdfFindReplace.Execute(
    "contract.pdf", "updated.pdf",
    "Short Name", "A Much Longer Replacement Name That Needs Fitting",
    options);

// Color replacement text and add a highlight background
var result = PdfFindReplace.Execute(
    "input.pdf", "output.pdf",
    "old text", "new text",
    new PdfFindReplaceOptions
    {
        ReplacementTextColor = PdfColor.Red,         // Font color of replaced text
        ReplacementHighlightColor = PdfColor.Yellow   // Background highlight behind text
    });

// Merge multiple PDFs into one, preserving page dimensions and resources
byte[] merged = PdfMerger.Merge(new[] { "cover.pdf", "report.pdf", "appendix.pdf" });
File.WriteAllBytes("combined.pdf", merged);

// Or write directly to a file
PdfMerger.MergeToFile(new[] { "file1.pdf", "file2.pdf" }, "merged.pdf");

// Merge with page range selection
byte[] selected = PdfMerger.Merge(new[]
{
    new PdfMergeInput(File.ReadAllBytes("doc1.pdf"), new[] { 1, 3, 5 }),
    new PdfMergeInput(File.ReadAllBytes("doc2.pdf"))  // all pages
});

// Split into individual pages
List<byte[]> pages = PdfSplitter.Split("input.pdf");

// Extract specific pages (1-based)
byte[] subset = PdfSplitter.ExtractPages("input.pdf", new[] { 1, 3, 5 });

// Split to individual files with naming pattern
PdfSplitter.SplitToFiles("input.pdf", "page_{0}.pdf");

byte[] pdf = PdfBuilder.Create()
    .WithMetadata(m => m.Title("Report").Author("Exis"))
    .AddPage(page => page
        .Size(PdfPageSize.A4)
        .AddText("Hello, World!", x: 72, y: 750, fontSize: 24,
            options: o => o.Font("Helvetica").Bold().Color(0, 0, 0.8))
        .AddText("Generated with Exis.PdfEditor", x: 72, y: 720, fontSize: 12)
        .AddLine(72, 710, 523, 710, strokeWidth: 1)
        .AddRectangle(72, 600, 200, 80, fill: true,
            fillRed: 0.95, fillGreen: 0.95, fillBlue: 1.0)
        .AddImage(jpegBytes, x: 300, y: 400, width: 200, height: 150))
    .AddPage(page => page
        .Size(PdfPageSize.Letter)
        .AddText("Page 2", x: 72, y: 700, fontSize: 14))
    .Build();

File.WriteAllBytes("output.pdf", pdf);

// Extract all text from a PDF
PdfTextResult text = PdfTextExtractor.ExtractText("input.pdf");
Console.WriteLine(text.FullText);

// Extract from specific pages only
PdfTextResult partial = PdfTextExtractor.ExtractText("input.pdf", new[] { 1, 3 });

// Structured extraction with position and font data
PdfStructuredTextResult structured = PdfTextExtractor.ExtractStructured("input.pdf");
foreach (var block in structured.Pages[0].TextBlocks)
    Console.WriteLine($"[{block.X:F0},{block.Y:F0}] {block.Text} " +
        $"(font={block.FontName}, size={block.FontSize})");

PdfDocumentInfo info = PdfInspector.Inspect("input.pdf");

Console.WriteLine($"Pages: {info.PageCount}");
Console.WriteLine($"Title: {info.Title}");
Console.WriteLine($"Fonts: {string.Join(", ", info.FontsUsed)}");
Console.WriteLine($"Encrypted: {info.IsEncrypted}");
Console.WriteLine($"Form fields: {info.FormFieldCount}");

// Find all images in a PDF
var found = PdfImageEditor.FindImages("input.pdf");
foreach (var img in found.Images)
    Console.WriteLine($"Image #{img.Index}: {img.PixelWidth}x{img.PixelHeight} " +
        $"{img.ColorSpace} {img.Format} on page(s) {string.Join(", ", img.PageNumbers)}");

// Replace all images with a new one
byte[] newLogo = File.ReadAllBytes("new-logo.jpg");
var result = PdfImageEditor.ReplaceAll("input.pdf", "output.pdf", newLogo);
Console.WriteLine($"Replaced {result.ImagesReplaced} of {result.ImagesFound} images");

// Replace specific images by index or page range
var selective = PdfImageEditor.Replace("input.pdf", "output.pdf", newLogo,
    new PdfImageReplaceOptions { ImageIndices = new[] { 0, 2 } });

byte[] pdf = PdfDocumentBuilder.Create()
    .PageSize(PdfPageSize.A4)
    .Margins(72)
    .WithMetadata(m => m.Title("Report").Author("Exis"))
    .Header(h => h
        .AddText("Quarterly Report", PdfHorizontalAlignment.Center, 12, o => o.Bold())
        .AddLine())
    .Footer(f => f
        .AddLine()
        .AddPageNumber())  // "Page 1 of 3"
    .AddParagraph("Introduction", 18, o => o.Bold())
    .AddSpacing(8)
    .AddParagraph("This report covers Q1 results.")
    .AddSpacing(12)
    .AddTable(t => t
        .Columns(2, 1, 1)
        .AlternatingRowBackground(0.95, 0.95, 1.0)
        .HeaderRow(r => r.AddCell("Product").AddCell("Units").AddCell("Revenue"))
        .AddRow(r => r.AddCell("Widget A").AddCell("1,200").AddCell("$24,000"))
        .AddRow(r => r.AddCell("Widget B").AddCell("850").AddCell("$17,000")))
    .AddPageBreak()
    .AddParagraph("Appendix", 14, o => o.Bold())
    .Build();

// Read form fields
List<PdfFormField> fields = PdfFormFiller.GetFields("form.pdf");
foreach (var field in fields)
    Console.WriteLine($"{field.Name} ({field.FieldType}) = {field.CurrentValue}");

// Fill fields
var result = PdfFormFiller.Fill("form.pdf", "filled.pdf", new Dictionary<string, string>
{
    { "FirstName", "John" },
    { "LastName", "Doe" },
    { "State", "CA" },
    { "AgreeToTerms", "Yes" }  // checkbox
});
Console.WriteLine($"Filled {result.FieldsFilled} fields");

// Flatten form (merge field appearances, remove interactive fields)
PdfFormFiller.Flatten("filled.pdf", "flattened.pdf");

var result = PdfRedactor.Redact("input.pdf", "redacted.pdf", new[]
{
    // Text-based redaction
    new PdfRedaction { Text = "CONFIDENTIAL" },

    // Regex pattern (e.g., SSN)
    new PdfRedaction { Text = @"\d{3}-\d{2}-\d{4}", IsRegex = true },

    // Replace with alternative text
    new PdfRedaction { Text = "SECRET", ReplaceWith = "[REDACTED]" },

    // Area-based redaction on specific page
    new PdfRedaction { PageNumber = 3, Area = new PdfRect(100, 200, 300, 50) }
});
Console.WriteLine($"Applied {result.RedactionsApplied} redactions");

var result = PdfOptimizer.Optimize("input.pdf", "optimized.pdf", new PdfOptimizeOptions
{
    CompressStreams = true,
    RemoveDuplicateObjects = true,
    RemoveMetadata = false,
    DownsampleImages = true,
    MaxImageDpi = 150
});
Console.WriteLine($"Saved {result.BytesSaved} bytes ({result.ReductionPercent:F1}%)");
Console.WriteLine($"Images downsampled: {result.ImagesDownsampled}");

using System.Security.Cryptography.X509Certificates;

// Sign a PDF
var cert = new X509Certificate2("certificate.pfx", "password");
PdfSigner.Sign("input.pdf", "signed.pdf", new PdfSignOptions
{
    Certificate = cert,
    Reason = "Approved",
    Location = "New York",
    ContactInfo = "admin@example.com"
});

// Verify a signed PDF
PdfSignatureInfo info = PdfSigner.Verify("signed.pdf");
Console.WriteLine($"Signed: {info.IsSigned}");
Console.WriteLine($"Valid: {info.IsValid}");
Console.WriteLine($"Signer: {info.SignerName}");
Console.WriteLine($"Certificate: {info.CertificateSubject}");
Console.WriteLine($"Issuer: {info.CertificateIssuer}");
Console.WriteLine($"Timestamp: {info.HasTimestamp}");

// Verify all signatures in a multi-signed document
List<PdfSignatureInfo> all = PdfSigner.VerifyAll("multi-signed.pdf");
foreach (var sig in all)
    Console.WriteLine($"{sig.SignerName}: valid={sig.IsValid}");

// Validate (no license required)
// Levels: PdfA1b, PdfA2b, PdfA2u, PdfA3b, PdfA3u
PdfAValidationResult result = PdfAConverter.Validate("input.pdf", PdfALevel.PdfA2b);
Console.WriteLine($"Compliant: {result.IsCompliant}");
foreach (var v in result.Violations)
    Console.WriteLine($"  [{v.Code}] {v.Message} (auto-fix: {v.CanAutoFix})");

// Convert to PDF/A
byte[] pdfa = PdfAConverter.Convert("input.pdf", PdfALevel.PdfA2b);
File.WriteAllBytes("output-pdfa.pdf", pdfa);

// All I/O operations have async overloads with CancellationToken support
byte[] merged = await PdfMerger.MergeAsync(inputPaths, cancellationToken);
PdfTextResult text = await PdfTextExtractor.ExtractTextAsync(stream, cancellationToken);
var info = await PdfInspector.InspectAsync(path, cancellationToken);
var result = await PdfOptimizer.OptimizeAsync(data, options, cancellationToken);
var sigs = await PdfSigner.VerifyAllAsync(path, cancellationToken);

// Pattern: ClassName.MethodNameAsync(...) on all classes