Add Watermark to PDF, Word, PPT, Excel Documents using C#

readme.md

Related blog post: Watermark Password Protected Documents using C#

AddImageWatermarkToPasswordProtectedDocument.cs

/*
 * Apply Image Watermark to document (PDF, Word, PPT, Excel, ...) using C#
 */
LoadOptions loadOptions = new LoadOptions();
loadOptions.Password = "P@$$w0rd";
string filePath = "path/document.docx";
using (Watermarker watermarker = new Watermarker(filePath, loadOptions))
{
    // Prepare Watermark Text and appearance. 
    ImageWatermark watermark = new ImageWatermark("watermark-logo.png")
    {
        Opacity = 0.7,
        X = 70,
        Y = 350
    };    
    // Add image watermark to document and save.
    watermarker.Add(watermark);
    watermarker.Save("path/watermark-document.docx");
}

AddTextWatermarkToPasswordProtectedDocument.cs

/*
 * Apply Text Watermark to document (PDF, Word, PPT, Excel, ...) using C#
 */
LoadOptions loadOptions = new LoadOptions();
loadOptions.Password = "P@$$w0rd";
string filePath = "path/document.pdf";
using (Watermarker watermarker = new Watermarker(filePath, loadOptions))
{
    // Prepare Watermark Text and appearance. 
    TextWatermark watermark = new TextWatermark("Watermark", new Font("Arial", 12))
    {
        RotateAngle = -45,
        Opacity = .3,
        ForegroundColor = Color.Red,
    };
    // Add watermark to document and save.
    watermarker.Add(watermark);
    watermarker.Save("path/watermark-document.pdf");
}