Following code snippet shows how to add text watermark to a document. If the document consists of multiple parts (pages, worksheets, slides, frames etc), the watermark will be added to all of them.
advanced_usage.adding_text_watermarks.AddTextWatermark
// Specify an absolute or relative path to your image. Ex: "C:\\Docs\\image.png" Watermarker watermarker = new Watermarker("image.png"); // Initialize the font to be used for watermark Font font = new Font("Arial", 19, FontStyle.Bold | FontStyle.Italic); // Create the watermark object TextWatermark watermark = new TextWatermark("Test watermark", font); // Set watermark properties watermark.... The values of all properties for absolute...); // Set absolute margins. Values are measured in document units...