Class WatermarkOptions

Namespace

CobaltPdf

Assembly

CobaltPdf.dll

Defines visual settings for a watermark injected into the generated PDF.

public class WatermarkOptions

Inheritance

object

WatermarkOptions

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

The watermark is rendered as HTML and positioned using a full-page overlay before the PDF is generated.

Properties

Color

Gets or sets an optional CSS color override for the watermark text.

public string? Color { get; set; }

Property Value

string

Remarks

When set, this overrides any color defined in the Html template. Accepts any valid CSS color value (e.g. "#ff0000", "rgba(0,0,0,0.5)", "red").

Horizontal

Gets or sets the horizontal alignment of the watermark within the page.

public HorizontalAlignment Horizontal { get; set; }

Property Value

HorizontalAlignment

Remarks

Controls whether the watermark is positioned at the left, center, or right of the page.

Html

Gets or sets the HTML markup used to render the watermark.

public string Html { get; set; }

Property Value

string

Remarks

This can include styled text, images, or inline CSS. For quick watermarks without custom HTML, use the WithText(string, WatermarkStyle) factory method instead.

Opacity

Gets or sets the opacity of the watermark.

public double Opacity { get; set; }

Property Value

double

Remarks

Valid values range from 0.0 (fully transparent) to 1.0 (fully opaque).

Rasterize

Gets or sets whether the watermark is flattened to a raster image baked into every page instead of injected as selectable text/vector content.

public bool Rasterize { get; set; }

Property Value

bool

Remarks

When true, the watermark is rendered to a transparent image and painted onto each page, so it can't be removed by selecting/deleting text in a PDF editor (there is no text run and no separate object to delete). Trade-offs: larger output, no selectable/searchable watermark text, and slight pixelation at deep zoom. This is tamper-resistance, not DRM — pixels baked into a page can still be cropped or painted over. Default false (the watermark stays crisp, selectable vector text).

Rotation

Gets or sets the rotation angle, in degrees, applied to the watermark.

public int Rotation { get; set; }

Property Value

int

Remarks

Positive values rotate clockwise; negative values rotate counterclockwise.

Vertical

Gets or sets the vertical alignment of the watermark within the page.

public VerticalAlignment Vertical { get; set; }

Property Value

VerticalAlignment

Remarks

Controls whether the watermark is positioned at the top, middle, or bottom of the page.

Methods

WithColor(string)

Sets the watermark text color, overriding any color in the Html template.

public WatermarkOptions WithColor(string cssColor)

Parameters

cssColor string

Any valid CSS color value (e.g. "#ff0000", "red", "rgba(0,0,0,0.5)").

Returns

WatermarkOptions

The same WatermarkOptions instance for chaining.

Examples

engine.WithWatermark(
    WatermarkOptions.WithText("DRAFT", WatermarkStyle.BoldStamp)
                    .WithColor("#e74c3c"));

WithHtml(string)

Replaces the generated HTML with a custom HTML/CSS snippet for full control.

public WatermarkOptions WithHtml(string html)

Parameters

html string

Raw HTML markup (may include inline CSS, images, etc.).

Returns

WatermarkOptions

The same WatermarkOptions instance for chaining.

WithOpacity(double)

Sets the opacity of the watermark.

public WatermarkOptions WithOpacity(double opacity)

Parameters

opacity double

A value from 0.0 (invisible) to 1.0 (fully opaque).

Returns

WatermarkOptions

The same WatermarkOptions instance for chaining.

WithPosition(WatermarkPosition)

Sets the watermark position using a single WatermarkPosition value.

public WatermarkOptions WithPosition(WatermarkPosition position)

Parameters

position WatermarkPosition

A combined position that maps to vertical and horizontal alignment.

Returns

WatermarkOptions

The same WatermarkOptions instance for chaining.

Examples

engine.WithWatermark(
    WatermarkOptions.WithText("CONFIDENTIAL", WatermarkStyle.SoftGray)
                    .WithPosition(WatermarkPosition.TopRight));

WithRasterize(bool)

Flattens the watermark to a raster image baked into every page so it can't be removed by selecting/deleting text in a PDF editor.

public WatermarkOptions WithRasterize(bool enable = true)

Parameters

enable bool

true to rasterize (default); false to keep the watermark as selectable vector text.

Returns

WatermarkOptions

The same WatermarkOptions instance for chaining.

Remarks

Tamper-resistance, not DRM: a baked-in image is much harder to remove than selectable text, but a determined user can still crop or paint over it.

WithRotation(int)

Sets the rotation angle of the watermark.

public WatermarkOptions WithRotation(int degrees)

Parameters

degrees int

Rotation in degrees. Negative values rotate counter-clockwise (e.g. -45).

Returns

WatermarkOptions

The same WatermarkOptions instance for chaining.

WithText(string, WatermarkStyle)

Creates a WatermarkOptions with a predefined visual style.

public static WatermarkOptions WithText(string text, WatermarkStyle style = WatermarkStyle.BoldStamp)

Parameters

text string

The watermark text (e.g. "DRAFT", "CONFIDENTIAL").

style WatermarkStyle

A predefined style that controls color, weight, rotation, and opacity.

Returns

WatermarkOptions

A fully configured WatermarkOptions ready to pass to WithWatermark.

Examples

engine.WithWatermark(WatermarkOptions.WithText("DRAFT", WatermarkStyle.RedDraft));