Part Four

Adding a text watermark. 

Please refer to Part One of this series to see the Word document output and calling code.

The TextWatermark class is standard code to add a watermark in a diagonal line.

Also note that it is also possible to add an image watermark.

This is the calling code which takes the following parameters:

  • Document to insert watermark into
    • Watermark text
    • Watermark font
    • Watermark fill colour
//// Add a text watermark
TextWatermark textWatermark = new TextWatermark();
textWatermark.AddWatermark(wordDoc, "DRAFT", "font-family:\"Calibri\";font-size:medium", "#C0C0C0");

Below is the class to add a text watermark.

The watermark transparency effect is governed by the falling code:

//// Switches on the transparency
Fill fill1 = new Fill() { Opacity = ".5" };


using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Web;
using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Vml;
using DocumentFormat.OpenXml.Vml.Office;
using DocumentFormat.OpenXml.Vml.Wordprocessing;
using DocumentFormat.OpenXml.Wordprocessing;
using HorizontalAnchorValues = DocumentFormat.OpenXml.Vml.Wordprocessing.HorizontalAnchorValues;
using Lock = DocumentFormat.OpenXml.Vml.Office.Lock;
using VerticalAnchorValues = DocumentFormat.OpenXml.Vml.Wordprocessing.VerticalAnchorValues;

namespace ExportToWord
{
    public class TextWatermark
    {
        /// <summary>
        /// Adds the watermark.
        /// </summary>
        /// <param name="doc">The document.</param>
        /// <param name="watermarkText">The watermark text.</param>
        /// <param name="watermarkStyle">The watermark style.</param>
        /// <param name="watermarkFillColor">Color of the watermark fill.</param>
        public void AddWatermark(WordprocessingDocument doc, string watermarkText, string watermarkStyle, string watermarkFillColor)
        {
            foreach (HeaderPart headerPart in doc.MainDocumentPart.HeaderParts)
            {
                SdtBlock sdtBlock1 = new SdtBlock();
                SdtProperties sdtProperties1 = new SdtProperties();
                SdtId sdtId1 = new SdtId() { Val = 87908844 };
                SdtContentDocPartObject sdtContentDocPartObject1 = new SdtContentDocPartObject();
                DocPartGallery docPartGallery1 = new DocPartGallery() { Val = "Watermarks" };
                DocPartUnique docPartUnique1 = new DocPartUnique();

                sdtContentDocPartObject1.Append(docPartGallery1);
                sdtContentDocPartObject1.Append(docPartUnique1);
                sdtProperties1.Append(sdtId1);
                sdtProperties1.Append(sdtContentDocPartObject1);

                SdtContentBlock sdtContentBlock1 = new SdtContentBlock();
                Paragraph paragraph2 = new Paragraph()
                {
                    RsidParagraphAddition = "00656E18",
                    RsidRunAdditionDefault = "00656E18"
                };

                ParagraphProperties paragraphProperties2 = new ParagraphProperties();
                ParagraphStyleId paragraphStyleId2 = new ParagraphStyleId() { Val = "Header" };
                paragraphProperties2.Append(paragraphStyleId2);

                Run run1 = new Run();
                RunProperties runProperties1 = new RunProperties();
                NoProof noProof1 = new NoProof();
                Languages languages1 = new Languages() { EastAsia = "zh-TW" };
                runProperties1.Append(noProof1);
                runProperties1.Append(languages1);
                Picture picture1 = new Picture();
                Shapetype shapetype1 = new Shapetype()
                {
                    Id = "_x0000_t136",
                    CoordinateSize = "21600,21600",
                    OptionalNumber = 136,
                    Adjustment = "10800",
                    EdgePath = "m@7,l@8,m@5,21600l@6,21600e"
                };

                Formulas formulas1 = new Formulas();
                Formula formula1 = new Formula() { Equation = "sum #0 0 10800" };
                Formula formula2 = new Formula() { Equation = "prod #0 2 1" };
                Formula formula3 = new Formula() { Equation = "sum 21600 0 @1" };
                Formula formula4 = new Formula() { Equation = "sum 0 0 @2" };
                Formula formula5 = new Formula() { Equation = "sum 21600 0 @3" };
                Formula formula6 = new Formula() { Equation = "if @0 @3 0" };
                Formula formula7 = new Formula() { Equation = "if @0 21600 @1" };
                Formula formula8 = new Formula() { Equation = "if @0 0 @2" };
                Formula formula9 = new Formula() { Equation = "if @0 @4 21600" };
                Formula formula10 = new Formula() { Equation = "mid @5 @6" };
                Formula formula11 = new Formula() { Equation = "mid @8 @5" };
                Formula formula12 = new Formula() { Equation = "mid @7 @8" };
                Formula formula13 = new Formula() { Equation = "mid @6 @7" };
                Formula formula14 = new Formula() { Equation = "sum @6 0 @5" };

                formulas1.Append(formula1);
                formulas1.Append(formula2);
                formulas1.Append(formula3);
               formulas1.Append(formula4);
                formulas1.Append(formula5);
                formulas1.Append(formula6);
                formulas1.Append(formula7);
                formulas1.Append(formula8);
                formulas1.Append(formula9);
                formulas1.Append(formula10);
                formulas1.Append(formula11);
                formulas1.Append(formula12);
                formulas1.Append(formula13);
                formulas1.Append(formula14);

                DocumentFormat.OpenXml.Vml.Path path1 = new DocumentFormat.OpenXml.Vml.Path()
                {
                    AllowTextPath = true,
                    ConnectionPointType = ConnectValues.Custom,
                    ConnectionPoints = "@9,0;@10,10800;@11,21600;@12,10800",
                    ConnectAngles = "270,180,90,0"
                };

                TextPath textPath1 = new TextPath()
                {
                    On = true,
                    FitShape = true
                };

                ShapeHandles shapeHandles1 = new ShapeHandles();

                ShapeHandle shapeHandle1 = new ShapeHandle() { Position = "#0,bottomRight", XRange = "6629,14971" };

                shapeHandles1.Append(shapeHandle1);

                var lock1 = new Lock
                {
                    Extension = ExtensionHandlingBehaviorValues.Edit,
                    TextLock = true,
                    ShapeType = true
                };

                shapetype1.Append(formulas1);
                shapetype1.Append(path1);
                shapetype1.Append(textPath1);
                shapetype1.Append(shapeHandles1);
                shapetype1.Append(lock1);

                //// Create the diagonal watermark shape
                Shape shape1 = new Shape()
                {
                    Id = "PowerPlusWaterMarkObject357476642",
                    Style = "position:absolute;left:0;text-align:left;margin-left:0;margin-top:0;width:527.85pt;height:131.95pt;rotation:315;z-index:-251656192;mso-position-horizontal:center;mso-position-horizontal-relative:margin;mso-position-vertical:center;mso-position-vertical-relative:margin",
                    OptionalString = "_x0000_s2049",
                    AllowInCell = true,
                    FillColor = watermarkFillColor,
                    Stroked = false,
                    Type = "#_x0000_t136"
                };

                //// Switches on the transparency
                Fill fill1 = new Fill() { Opacity = ".5" };

                //// Font Style and display text
                TextPath textPath2 = new TextPath()
                {
                    Style = watermarkStyle,
                    String = watermarkText
                };

                TextWrap textWrap1 = new TextWrap()
                {
                    AnchorX = HorizontalAnchorValues.Margin,
                    AnchorY = VerticalAnchorValues.Margin
                };

                shape1.Append(fill1);
                shape1.Append(textPath2);
                shape1.Append(textWrap1);
                picture1.Append(shapetype1);
                picture1.Append(shape1);
                run1.Append(runProperties1);
                run1.Append(picture1);
                paragraph2.Append(paragraphProperties2);
                paragraph2.Append(run1);
                sdtContentBlock1.Append(paragraph2);
                sdtBlock1.Append(sdtProperties1);
                sdtBlock1.Append(sdtContentBlock1);
                headerPart.Header.Append(sdtBlock1);
                headerPart.Header.Save();
            }
        }
    }
}