Watermarks in Rich Text Documents

• Dec 24, 2021
• 3 minutes to read

A watermark is a faded background image or text displayed behind document content. The WPF Rich Text Editor allows you to create and remove watermarks in DOCX, DOC, and RTF documents. You can also print and export documents with watermarks to PDF.

Create a Watermark

A watermark is located in the section header. If the document does not contain headers, you cannot add a watermark. Refer to the following article for an example on how to create headers: Headers and Footers

If the document has multiple sections, the WatermarkManager adds the same watermark to each section and to each available header type (first, primary, odd, or even).

The WatermarkManager.Type property indicates whether the document has watermarks. The property returns WatermarkType.None if the document does not contain watermarks.

Example: Create a Text Watermark

The code sample below adds a text watermark:

C#

using DevExpress.XtraRichEdit.API.Native;
using System.Drawing;

Document document = richEditControl.Document;
foreach (Section section in document.Sections)
{

    // Check whether the document sections have headers:
    if (!section.HasHeader(HeaderFooterType.Primary))
    {
        // If not, create an empty header
        SubDocument header = section.BeginUpdateHeader();
        section.EndUpdateHeader(header);
    }
}

TextWatermarkOptions textWatermarkOptions = new TextWatermarkOptions();
textWatermarkOptions.Color = Color.LightGray;
textWatermarkOptions.FontFamily = "Calibri";
textWatermarkOptions.Layout = WatermarkLayout.Horizontal;
textWatermarkOptions.Semitransparent = true;

document.WatermarkManager.SetText("CONFIDENTIAL", textWatermarkOptions);

VB.NET

Imports DevExpress.XtraRichEdit.API.Native
Imports System.Drawing

' Check whether the document sections have headers:
Private document As Document = richEditControl.Document
For Each section As Section In document.Sections
    If Not section.HasHeader(HeaderFooterType.Primary) Then
        ' If not, create an empty header
        Dim header As SubDocument = section.BeginUpdateHeader()
        section.EndUpdateHeader(header)
    End If
Next section

Dim textWatermarkOptions As New TextWatermarkOptions()
textWatermarkOptions.Color = Color.LightGray
textWatermarkOptions.FontFamily = "Calibri"
textWatermarkOptions.Layout = WatermarkLayout.Horizontal
textWatermarkOptions.Semitransparent = True

document.WatermarkManager.SetText("CONFIDENTIAL", textWatermarkOptions)

Example: Create an Image Watermark

The code sample below adds an image watermark:

C#

using DevExpress.XtraRichEdit.API.Native;
using System.Drawing;

Document document = richEditControl.Document;

// Check whether the document sections have headers:
foreach (Section section in document.Sections)
{
    if (!section.HasHeader(HeaderFooterType.Primary))
    {
        //If not, create an empty header
        SubDocument header = section.BeginUpdateHeader();
        section.EndUpdateHeader(header);
    }
}

ImageWatermarkOptions imageWatermarkOptions = new ImageWatermarkOptions();
imageWatermarkOptions.Washout = false;
imageWatermarkOptions.Scale = 2;
document.WatermarkManager.SetImage(Image.FromFile("Documents//DevExpress.png"),
     imageWatermarkOptions);

VB.NET

Imports DevExpress.XtraRichEdit.API.Native
Imports System.Drawing

Private document As Document = richEditControl.Document

' Check whether the document sections have headers:
For Each section As Section In document.Sections
    If Not section.HasHeader(HeaderFooterType.Primary) Then
        ' If not, create an empty header
        Dim header As SubDocument = section.BeginUpdateHeader()
        section.EndUpdateHeader(header)
    End If
Next section

Dim imageWatermarkOptions As New ImageWatermarkOptions()
imageWatermarkOptions.Washout = False
imageWatermarkOptions.Scale = 2
document.WatermarkManager.SetImage(Image.FromFile("Documents//DevExpress.png"), imageWatermarkOptions)

Remove the Watermark

The code sample below checks the watermark type and removes it:

C#

richEditControl.LoadDocument("FirstLook.docx");
WatermarkManager watermarkManager = 
    richEditControl.Document.WatermarkManager;
if (watermarkManager.Type == WatermarkType.Image)
{
    watermarkManager.Remove();
}
richEditControl.SaveDocument("FirstLook_new.docx", DocumentFormat.OpenXml);

VB.NET

richEditControl.LoadDocument("FirstLook.docx")
Dim watermarkManager As WatermarkManager = richEditControl.Document.WatermarkManager
If watermarkManager.Type = WatermarkType.Image Then
    watermarkManager.Remove()
End If
richEditControl.SaveDocument("FirstLook_new.docx", DocumentFormat.OpenXml)

Limitations

The following features are not available:

• User Interface elements to organize watermarks.
• Edit an existing watermark. Recreate the watermark with new parameters to change it.

• Add different watermarks to document sections. Insert regular shapes (TextBox or Image) in the headers of the separate sections. Refer to the following example:

  View Example: How to add a watermark with a text or image to the document