### Initialize a PDFDocument

Source: https://pdfkit.org/docs/getting_started.html

Basic setup for requiring the module and instantiating a new PDF document.

```javascript
const PDFDocument = require('pdfkit');
const doc = new PDFDocument();
```

--------------------------------

### Install PDFKit via npm

Source: https://pdfkit.org/index.html

Use this command to install the PDFKit package in your project.

```bash
npm install pdfkit
```

--------------------------------

### Example: Adding Multiple Annotations

Source: https://pdfkit.org/docs/annotations.html

Demonstrates how to add various annotations, including links, highlights, strike-throughs, and notes, with custom colors and icons.

```javascript
doc.fontSize(25)
   .fillColor('blue')
   .text('This is a link!', 20, 0);

const width = doc.widthOfString('This is a link!');
const height = doc.currentLineHeight();

doc.underline(20, 0, width, height, {color: 'blue'})
   .link(20, 0, width, height, 'http://google.com/');

doc.moveDown()
   .fillColor('black')
   .highlight(20, doc.y, doc.widthOfString('This text is highlighted!'), height)
   .text('This text is highlighted!');

doc.addSpotColor('PANTONE185C', 0, 100, 78, 9)
   .moveDown()
   .fillColor('PANTONE185C')
   .text('This text uses spot color!');

doc.moveDown()
   .strike(20, doc.y, doc.widthOfString('STRIKE!'), height)
   .text('STRIKE!');

doc.note(10, 30, 30, 30, "Text of note");

doc.note(10, 80, 30, 30, "Text of custom note", {Name: 'Key', color: 'red'});

doc.goTo(20, doc.y, 10, 20, 'LINK', {});
```

--------------------------------

### Example: Combined Text Formatting and Annotations

Source: https://pdfkit.org/docs/annotations.html

Shows how to apply text formatting, including links and underlines, directly within the `text` method.

```javascript
doc.fontSize(20)
   .fillColor('red')
   .text('Another link!', 20, 0, {
     link: 'http://apple.com/',
     underline: true
   });
```

--------------------------------

### Adding and Scaling Images in PDFKit

Source: https://pdfkit.org/docs/images.html

Examples of using the image method with various scaling, fitting, and alignment options.

```javascript
// Scale proprotionally to the specified width
doc.image('images/test.jpeg', 0, 15, {width: 300})
   .text('Proportional to width', 0, 0);

// Fit the image within the dimensions
doc.image('images/test.jpeg', 320, 15, {fit: [100, 100]})
   .rect(320, 15, 100, 100)
   .stroke()
   .text('Fit', 320, 0);

// Stretch the image
doc.image('images/test.jpeg', 320, 145, {width: 200, height: 100})
   .text('Stretch', 320, 130);

// Scale the image
doc.image('images/test.jpeg', 320, 280, {scale: 0.25})
   .text('Scale', 320, 265);

// Fit the image in the dimensions, and center it both horizontally and vertically
doc.image('images/test.jpeg', 430, 15, {fit: [100, 100], align: 'center', valign: 'center'})
   .rect(430, 15, 100, 100).stroke()
   .text('Centered', 430, 0);
```

--------------------------------

### Style Precedence Example

Source: https://pdfkit.org/docs/table.html

Shows the order of precedence for styles when defining a table: `defaultStyle`, `columnStyles`, `rowStyles`, and `cellStyle`. The resulting cell style is a combination of these.

```javascript
doc.table({
  defaultStyle: { border: 1 },
  columnStyles: { border: { right: 2 } },
  rowStyles: { border: { bottom: 3 } },
  data: [
    [{ border: { left: 4 } }]
  ]
})
```

--------------------------------

### Add Link and Underline Annotations to Text

Source: https://pdfkit.org/docs/annotations.html

A simplified example showing how to add both a link and an underline to a piece of text using a single options object. This is useful for common text annotations.

```javascript
doc.fontSize(20)
   .fillColor('red')
   .text('Another link!', 20, 0, {
     link: 'http://apple.com/',
     underline: true
   }
);
```

--------------------------------

### Table with Row and Column Spans

Source: https://pdfkit.org/docs/table.html

Illustrates creating a table with cells that span multiple rows and columns, using `rowSpan` and `colSpan` properties. This example also sets a `defaultStyle` for the table.

```javascript
doc.table({
  defaultStyle: { border: false, width: 60 },
  data: [
    ["", "column 1", "column 2", "column 3"],
    [
      "row 1",
      {
        rowSpan: 3,
        colSpan: 3,
        border: true,
        backgroundColor: "#ccc",
        text: "rowSpan: 3\ncolSpan: 3\n\nborder:\n[true, true, true, true]",
      },
    ],
    ["row 2"],
    ["row 3"],
  ],
})
```

--------------------------------

### Wrap and justify text in PDFKit

Source: https://pdfkit.org/docs/text.html

Configure text wrapping and justification by passing an options object to the `text` method. Options include `width`, `align`, and `lineBreak`. This example demonstrates left, center, right, and justified alignment.

```javascript
const lorem = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam in suscipit purus.  Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Vivamus nec hendrerit felis. Morbi aliquam facilisis risus eu lacinia. Sed eu leo in turpis fringilla hendrerit. Ut nec accumsan nisl.';

doc.fontSize(8);
doc.text(`This text is left aligned. ${lorem}`, {
  width: 410,
  align: 'left'
}
);

doc.moveDown();
doc.text(`This text is centered. ${lorem}`, {
  width: 410,
  align: 'center'
}
);

doc.moveDown();
doc.text(`This text is right aligned. ${lorem}`, {
  width: 410,
  align: 'right'
}
);

doc.moveDown();
doc.text(`This text is justified. ${lorem}`, {
  width: 410,
  align: 'justify'
}
);

// draw bounding rectangle
doc.rect(doc.x, 0, 410, doc.y).stroke();
```

--------------------------------

### Apply Gradient Fill

Source: https://pdfkit.org/examples/browserify/browser.html

Creates and applies a linear gradient fill to a rectangular shape. Define the gradient's start and end points, and use `stop()` to specify colors at different positions.

```javascript
// a gradient fill
var gradient = doc
.linearGradient(100, 300, 200, 300)
.stop(0, 'green')
.stop(0.5, 'red')
.stop(1, 'green');
doc.rect(100, 300, 100, 100).fill(gradient);
```

--------------------------------

### Light Horizontal Lines for Table Rows in PDFKit

Source: https://pdfkit.org/docs/table.html

Create subtle horizontal lines for table rows using `rowStyles`. This example applies a thicker black border to the header and thinner gray borders to subsequent rows.

```javascript
doc.table({
  rowStyles: (i) => {
    return i < 1
      ? { border: [0, 0, 2, 0], borderColor: "black" }
      : { border: [0, 0, 1, 0], borderColor: "#aaa" };
  },
  data: [
    ["Header 1", "Header 2", "Header 3"],
    ["Sample value 1", "Sample value 2", "Sample value 3"],
    ["Sample value 1", "Sample value 2", "Sample value 3"],
    ["Sample value 1", "Sample value 2", "Sample value 3"],
    ["Sample value 1", "Sample value 2", "Sample value 3"],
    ["Sample value 1", "Sample value 2", "Sample value 3"],
  ],
})
```

--------------------------------

### goTo

Source: https://pdfkit.org/docs/destinations.html

Creates a link to a previously defined named destination.

```APIDOC
## goTo(x, y, width, height, destination)

### Description
Creates an annotation that acts as a link to a specific named destination.

### Parameters
- **x** (number) - Required - X coordinate of the link area.
- **y** (number) - Required - Y coordinate of the link area.
- **width** (number) - Required - Width of the link area.
- **height** (number) - Required - Height of the link area.
- **destination** (string) - Required - The name of the destination to link to.
```

--------------------------------

### Navigate to Destinations

Source: https://pdfkit.org/docs/destinations.html

Use goTo to create interactive links that jump to previously defined named destinations.

```javascript
// Go to annotation
doc.goTo(10, 10, 100, 20, 'LINK')

// Go to annotation for this text
doc.text('Another goto', 20, 0, {
  goTo: 'ENDP',
  underline: true
});
```

--------------------------------

### Generate a PDF document

Source: https://pdfkit.org/index.html

Demonstrates creating a document, piping output to a file, embedding fonts, adding images, drawing vector graphics, and adding annotations.

```javascript
const PDFDocument = require('pdfkit'); const fs = require('fs');
// Create a document const doc = new PDFDocument();
// Pipe its output somewhere, like to a file or HTTP response // See below for browser usage doc.pipe(fs.createWriteStream('output.pdf'));
// Embed a font, set the font size, and render some text doc .font('fonts/PalatinoBold.ttf') .fontSize(25) .text('Some text with an embedded font!', 100, 100);
// Add an image, constrain it to a given size, and center it vertically and horizontally doc.image('path/to/image.png', { fit: [250, 300], align: 'center', valign: 'center' });
// Add another page doc .addPage() .fontSize(25) .text('Here is some vector graphics...', 100, 100);
// Draw a triangle doc .save() .moveTo(100, 150) .lineTo(100, 250) .lineTo(200, 250) .fill('#FF3300');
// Apply some transforms and render an SVG path with the 'even-odd' fill rule doc .scale(0.6) .translate(470, -380) .path('M 250,75 L 323,301 131,161 369,161 177,301 z') .fill('red', 'even-odd') .restore();
// Add some text with annotations doc .addPage() .fillColor('blue') .text('Here is a link!', 100, 100) .underline(100, 100, 160, 27, { color: '#0000FF' }) .link(100, 100, 160, 27, 'http://google.com/');
// Finalize PDF file doc.end();
```

--------------------------------

### Wrap Text into Columns

Source: https://pdfkit.org/examples/browserify/browser.html

Adds wrapped text to the PDF, starting at a specified position. Subsequent text can be styled with a different font and size, and positioned using `moveDown()`.

```javascript
// and some justified text wrapped into columns
doc
.text('And here is some wrapped text...', 100, 450)
.font('Times-Roman', 13)
.moveDown()
```

--------------------------------

### Set Font and Font Size

Source: https://pdfkit.org/docs/text.html

Demonstrates setting the font size and then switching between standard PDF fonts and embedded TrueType or collection fonts. Ensure font files are accessible by path.

```javascript
// Set the font size
doc.fontSize(18);

// Using a standard PDF font
doc.font('Times-Roman')
   .text('Hello from Times Roman!')
   .moveDown(0.5);

// Using a TrueType font (.ttf)
doc.font('fonts/GoodDog.ttf')
   .text('This is Good Dog!')
   .moveDown(0.5);

// Using a collection font (.ttc or .dfont)
doc.font('fonts/Chalkboard.ttc', 'Chalkboard-Bold')
   .text('This is Chalkboard, not Comic Sans.');
```

--------------------------------

### Cancel Link in Rich Text

Source: https://pdfkit.org/docs/text.html

To remove a hyperlink from subsequent text, set the `link` option to `null` in the `text` method. This example demonstrates changing colors and applying/removing links.

```javascript
doc.fillColor('red')
   .text(lorem.slice(0, 199), {
     width: 465,
     continued: true
   })
   .fillColor('blue')
   .text(lorem.slice(199, 282), {
     link: 'http://www.example.com',
     continued: true
   })
   .fillColor('green')
   .text(lorem.slice(182, 400), {
     link: null
   });
```

--------------------------------

### Create a Simple Table

Source: https://pdfkit.org/docs/table.html

Define a basic table with data. Alternatively, use the row-by-row method for more control.

```javascript
doc.table({
    data: [
        ['Column 1', 'Column 2', 'Column 3'],
        ['One value goes here', 'Another one here', 'OK?']
    ]
})
```

```javascript
doc.table()
   .row(['Column 1', 'Column 2', 'Column 3'])
   .row(['One value goes here', 'Another one here', 'OK?'])
```

--------------------------------

### Browser PDFKit with blob-stream

Source: https://pdfkit.org/index.html

Use this snippet to integrate PDFKit in the browser with Browserify or webpack. It requires the blob-stream module to handle PDF output as a Blob. Ensure you have the necessary dependencies installed.

```javascript
require('pdfkit');
const blobStream = require('blob-stream');

const doc = new PDFDocument();
const stream = doc.pipe(blobStream());

doc.end();
stream.on('finish', function() {
  const blob = stream.toBlob('application/pdf');
  const url = stream.toBlobURL('application/pdf');
  iframe.src = url;
});
```

--------------------------------

### Equivalent Structure Construction for Text

Source: https://pdfkit.org/docs/accessibility.html

This demonstrates the manual equivalent of using `structParent` with `text()`, showing how paragraphs are added as 'P' type structure elements.

```javascript
const section = doc.struct('Sect');
doc.addStructure(section);
section.add(doc.struct('P', () => { doc.text("Foo. "); });
section.add(doc.struct('P', () => { doc.text("Bar. "); });
```

--------------------------------

### List Creation

Source: https://pdfkit.org/docs/text.html

How to create bulleted lists, including multi-level lists and custom styling.

```APIDOC
## Lists

The `list` method generates bulleted lists. It accepts an array of strings and optional `x`, `y` coordinates.

### Options:
- `bulletRadius` (number): The radius of the bullet.
- `textIndent` (number): Indentation for the list text.
- `bulletIndent` (number): Indentation for the bullet itself.

Nested arrays can be used to create multi-level lists.

### Example:
```javascript
doc.list(['Item 1', 'Item 2', ['Subitem 2.1', 'Subitem 2.2'], 'Item 3']);
```
```

--------------------------------

### Apply multi-column text layout

Source: https://pdfkit.org/docs/text.html

Demonstrates wrapping text into multiple columns with specific dimensions and alignment.

```javascript
const lorem = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Etiam in suscipit purus. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Vivamus nec hendrerit felis. Morbi aliquam facilisis risus eu lacinia. Sed eu leo in turpis fringilla hendrerit. Ut nec accumsan nisl. Suspendisse rhoncus nisl posuere tortor tempus et dapibus elit porta. Cras leo neque, elementum a rhoncus ut, vestibulum non nibh. Phasellus pretium justo turpis. Etiam vulputate, odio vitae tincidunt ultricies, eros odio dapibus nisi, ut tincidunt lacus arcu eu elit. Aenean velit erat, vehicula eget lacinia ut, dignissim non tellus. Aliquam nec lacus mi, sed vestibulum nunc. Suspendisse potenti. Curabitur vitae sem turpis. Vestibulum sed neque eget dolor dapibus porttitor at sit amet sem. Fusce a turpis lorem. Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae;';

doc.text(lorem, {
  columns: 3,
  columnGap: 15,
  height: 100,
  width: 465,
  align: 'justify'
});
```

--------------------------------

### Draw a Path with Lines and Curves in PDFKit

Source: https://pdfkit.org/docs/vector.html

Use moveTo, lineTo, quadraticCurveTo, and bezierCurveTo to define a path. All methods are chainable. The path is stroked to be visible.

```javascript
doc.moveTo(0, 20)                               // set the current point
   .lineTo(100, 160)                            // draw a line
   .quadraticCurveTo(130, 200, 150, 120)        // draw a quadratic curve
   .bezierCurveTo(190, -40, 200, 200, 300, 150) // draw a bezier curve
   .lineTo(400, 90)                             // draw another line
   .stroke();                                   // stroke the path
```

--------------------------------

### Create PDF Document and Pipe to Blob Stream

Source: https://pdfkit.org/examples/browserify/browser.html

Initializes a new PDFDocument and pipes its output to a blob stream for browser-based PDF generation. Ensure blob-stream is available in your environment.

```javascript
// create a document and pipe to a blob
var doc = new PDFDocument();
var stream = doc.pipe(blobStream());
```

--------------------------------

### Initializing Form Support

Source: https://pdfkit.org/docs/forms.html

Before adding any form annotations, you must initialize the form functionality for the document.

```APIDOC
## Initialize Form Support

### Description
Initializes the PDF document to support form annotations. This method must be called before adding any form fields.

### Method
`initForm()`

### Endpoint
N/A (Method on document object)

### Parameters
None

### Request Example
```javascript
doc.font('Helvetica'); // establishes the default form field font
doc.initForm();
```

### Response
N/A
```

--------------------------------

### Add hierarchical bookmarks in PDFKit

Source: https://pdfkit.org/docs/outline.html

Demonstrates creating a top-level bookmark and a nested sub-section using the outline root.

```javascript
// Get a reference to the Outline root
const { outline } = doc;

// Add a top-level bookmark
const top = outline.addItem('Top Level');

// Add a sub-section
top.addItem('Sub-section');
```

--------------------------------

### Deferred Content Execution with Closures

Source: https://pdfkit.org/docs/accessibility.html

Demonstrates using closures to defer content addition until the structure element is attached to the document.

```javascript
const myParagraph = doc.struct('P', [
    () => { doc.text("Please see ", { continued: true }); },
    doc.struct('Link', () => {
        doc.text("something", { link: "http://www.example.com/", continued: true });
    }),
    () => { doc.text(" for details. ", { link: null }); }
]);
```

```javascript
doc.addStructure(section1);
section1.add(myParagraph); // Content is added now
```

```javascript
section1.add(myParagraph);
doc.addStructure(section1); // Content is added now
```

--------------------------------

### Table Options

Source: https://pdfkit.org/docs/table.html

Lists and describes the available options for configuring a table.

```APIDOC
## Table options
  * `position` - The position of the table (default `{x: doc.x, y: doc.y}`)
  * `maxWidth` - The maximum width the table can expand to (defaults to the remaining content width (offset from the tables position))
  * `columnStyles` - Column definitions of the table. (default `auto`)
  * `rowStyles` - Row definitions of the table. (default `*`)
  * `defaultStyle` - Defaults to apply to every cell
  * `data` - The data to render (not required, you can call `.row()`). This can be an iterable (async or sync)
  * `debug` - Whether to show the debug lines for all the cells (default `false`)
```

--------------------------------

### Create Dashed Lines with PDFKit

Source: https://pdfkit.org/docs/vector.html

Use the `dash` method to create dashed lines. Specify dash length and optional space and phase. Use `undash` to return to solid lines.

```javascript
doc.circle(100, 50, 50)
   .dash(5, {space: 10})
   .stroke();
```

--------------------------------

### Initialize PDF Forms

Source: https://pdfkit.org/docs/forms.html

Call initForm() before adding any form annotations to the document.

```javascript
doc.font('Helvetica'); // establishes the default form field font doc.initForm(); 
```

--------------------------------

### Configure Line Cap and Line Join Styles in PDFKit

Source: https://pdfkit.org/docs/vector.html

Demonstrates different line cap styles (butt, round, square) and line join styles (miter, round, bevel) by setting the respective properties and drawing shapes. A large line width is used for better visualization.

```javascript
// these examples are easier to see with a large line width
doc.lineWidth(25);

// line cap settings
doc.lineCap('butt')
   .moveTo(50, 20)
   .lineTo(100, 20)
   .stroke();

doc.lineCap('round')
   .moveTo(150, 20)
   .lineTo(200, 20)
   .stroke();

// square line cap shown with a circle instead of a line so you can see it
doc.lineCap('square')
   .moveTo(250, 20)
   .circle(275, 30, 15)
   .stroke();

// line join settings
doc.lineJoin('miter')
   .rect(50, 100, 50, 50)
   .stroke();

doc.lineJoin('round')
   .rect(150, 100, 50, 50)
   .stroke();

doc.lineJoin('bevel')
   .rect(250, 100, 50, 50)
   .stroke();
```

--------------------------------

### Incremental Structure Construction

Source: https://pdfkit.org/docs/accessibility.html

Illustrates building structure elements incrementally and ending them to free memory.

```javascript
// Begin a new section and add it to the document's structure
const mySection = doc.struct('Sect');
doc.addStructure(mySection);

// Create a new paragraph and add it to the section
const myParagraph = doc.struct('P');
mySection.add(myParagraph);

// Add content, both to the page, and the paragraph
const myParagraphContent = doc.markStructureContent('P');
myParagraph.add(myParagraphContent);
doc.text('Hello, world! ');

// End the paragraph, allowing it to be flushed out, freeing memory
myParagraph.end();
```

--------------------------------

### Generate PDF content in the browser

Source: https://pdfkit.org/demo/browser.html

Initializes a PDF document and pipes it to a blob stream for browser-based output.

```javascript
// create a document and pipe to a blob
var doc = new PDFDocument();
var stream = doc.pipe(blobStream());
// draw some text
doc.fontSize(25).text('Here is some vector graphics...', 100, 80);
// some vector graphics
doc
.save()
.moveTo(100, 150)
.lineTo(100, 250)
.lineTo(200, 250)
.fill('#FF3300');
doc.circle(280, 200, 50).fill('#6600FF');
// an SVG path
doc
.scale(0.6)
.translate(470, 130)
.path('M 250,75 L 323,301 131,161 369,161 177,301 z')
.fill('red', 'even-odd')
.restore();
doc.save();
// a gradient fill
var gradient = doc
.linearGradient(100, 300, 200, 300)
.stop(0, 'green')
.stop(0.5, 'red')
.stop(1, 'green');
doc.rect(100, 300, 100, 100).fill(gradient);
// stroke & fill uncolored tiling pattern
var stripe45d = doc.pattern(
[1, 1, 4, 4],
3,
3,
'1 w 0 1 m 4 5 l s 2 0 m 5 3 l s'
);
doc.circle(280, 350, 50).fill([stripe45d, 'blue']);
doc
.rect(380, 300, 100, 100)
.fillColor('lime')
.strokeColor([stripe45d, 'orange'])
.lineWidth(5)
.fillAndStroke();
doc.restore();
// and some justified text wrapped into columns
doc
.text('And here is some wrapped text...', 100, 450)
.font('Times-Roman', 13)
.moveDown()
```

--------------------------------

### Table with Optional Borders

Source: https://pdfkit.org/docs/table.html

Demonstrates how to apply optional borders to table cells using various configurations.

```APIDOC
## Optional border
```javascript
doc.table({
  data: [
    [
      { border: [true, false, false, false], backgroundColor: "#eee", text: "border:\n[true, false, false, false]" },
      { border: false, backgroundColor: "#ddd", text: "border:\nfalse" },
      { border: true, backgroundColor: "#eee", text: "border:\ntrue" },
    ],
    [
      { rowSpan: 3, border: true, backgroundColor: "#eef", text: "rowSpan: 3\n\nborder:\ntrue" },
      { border: undefined, backgroundColor: "#eee", text: "border:\nundefined (default)" },
      { border: [false, false, false, true], backgroundColor: "#ddd", text: "border:\n[false, false, false, true]" },
    ],
    [
      { colSpan: 2, border: true, backgroundColor: "#efe", text: "colSpan: 2\n\nborder:\ntrue" },
    ],
    [
      { border: 0, backgroundColor: "#eee", text: "border:\n0 (same as false)" },
      { border: [false, true, true, false], backgroundColor: "#ddd", text: "border:\n[false, true, true, false]" },
    ],
  ],
})
```
```

--------------------------------

### Create a Text Field

Source: https://pdfkit.org/docs/forms.html

Adds a text field with specific formatting options.

```javascript
doc.formText('leaf2', 10, 60, 200, 40, {   multiline: true,   align: 'right',   format: {     type: 'date',     params: 'm/d'   } }); 
```

--------------------------------

### Apply Winding Rules for Path Filling in PDFKit

Source: https://pdfkit.org/docs/vector.html

Use winding rules 'non-zero' or 'even-odd' with `fill` or `fillAndStroke` to control how paths are filled. Transformations like `translate` and `scale` can be applied before drawing.

```javascript
// Initial setup
doc.fillColor('red')
   .translate(-100, -50)
   .scale(0.8);

// Draw the path with the non-zero winding rule
doc.path('M 250,75 L 323,301 131,161 369,161 177,301 z')
   .fill('non-zero');

// Draw the path with the even-odd winding rule
doc.translate(280, 0)
   .path('M 250,75 L 323,301 131,161 369,161 177,301 z')
   .fill('even-odd');
```

--------------------------------

### Define Table with Optional Borders

Source: https://pdfkit.org/docs/table.html

Demonstrates how to define a table with various border configurations for individual cells, including boolean, array, and numeric values for the `border` property.

```javascript
doc.table({
  data: [
    [
      { border: [true, false, false, false], backgroundColor: "#eee", text: "border:\n[true, false, false, false]" },
      { border: false, backgroundColor: "#ddd", text: "border:\nfalse" },
      { border: true, backgroundColor: "#eee", text: "border:\ntrue" },
    ],
    [
      { rowSpan: 3, border: true, backgroundColor: "#eef", text: "rowSpan: 3\n\nborder:\ntrue" },
      { border: undefined, backgroundColor: "#eee", text: "border:\nundefined (default)" },
      { border: [false, false, false, true], backgroundColor: "#ddd", text: "border:\n[false, false, false, true]" },
    ],
    [
      { colSpan: 2, border: true, backgroundColor: "#efe", text: "colSpan: 2\n\nborder:\ntrue" },
    ],
    [
      { border: 0, backgroundColor: "#eee", text: "border:\n0 (same as false)" },
      { border: [false, true, true, false], backgroundColor: "#ddd", text: "border:\n[false, true, true, false]" },
    ],
  ],
})
```

--------------------------------

### Number and Percent Formatting

Source: https://pdfkit.org/docs/forms.html

Details options for formatting numeric fields, including decimal places, separators, negative number styles, and currency.

```APIDOC
## Number and percent format
  * `format.nDec` [_number_] - the number of places after the decimal point
  * `format.sepComma` [_boolean_] - display a comma separator, otherwise do not display a separator.
  * `format.negStyle` _string_ - the value must be one of `MinusBlack` , `Red`, `ParensBlack`, `ParensRed`
  * `format.currency` _string_ - a currency symbol to display
  * `format.currencyPrepend` _boolean_ - set to true to prepend the currency symbol

```javascript
// Currency text field formatting
doc.formText('leaf2', 10, 60, 200, 40, {
  multiline: true,
  align: 'right',
  format: {
    type: 'number',
    nDec: 2,
    sepComma: true,
    negStyle: 'ParensRed',
    currency: '$',
    currencyPrepend: true
  }
});
```
```

--------------------------------

### Create Linear and Radial Gradients in PDFKit

Source: https://pdfkit.org/docs/vector.html

Create gradient fills using `linearGradient` or `radialGradient`. Define color stops with percentage, color, and optional opacity. Gradients are applied using `fill` or `fillColor`.

```javascript
// Create a linear gradient
let grad = doc.linearGradient(50, 0, 150, 100);
grad.stop(0, 'green')
    .stop(1, 'red');

doc.rect(50, 0, 100, 100);
doc.fill(grad);

// Create a radial gradient
grad = doc.radialGradient(300, 50, 0, 300, 50, 50);
grad.stop(0, 'orange', 0)
    .stop(1, 'orange', 1);

doc.circle(300, 50, 50);
doc.fill(grad);
```

--------------------------------

### Configure expanded bookmarks in PDFKit

Source: https://pdfkit.org/docs/outline.html

Uses the expanded option to ensure child bookmarks are visible by default when the parent is added.

```javascript
// Add a top-level bookmark
const top = outline.addItem('Top Level', { expanded: true });

// Add a sub-section
top.addItem('Sub-section');
```

--------------------------------

### Encryption and Access Privileges

Source: https://pdfkit.org/docs/getting_started.html

Configure PDF encryption and permission settings using the options object during PDFDocument creation.

```APIDOC
## Encryption and Access Privileges

### Description
Enable encryption and set access permissions for the PDF file.

### Request Body
- **userPassword** (string) - Optional - Password required to open the file
- **ownerPassword** (string) - Optional - Password for full access and permission management
- **pdfVersion** (string) - Optional - PDF version (1.3, 1.4, 1.5, 1.6, 1.7, 1.7ext3)
- **permissions** (object) - Optional - Object specifying file permissions

### Permissions Object
- **printing** (string) - Optional - "lowResolution" or "highResolution"
- **modifying** (boolean) - Optional - Allow modifying document content
- **copying** (boolean) - Optional - Allow copying text or graphics
- **annotating** (boolean) - Optional - Allow annotating and form filling
- **fillingForms** (boolean) - Optional - Allow filling in form fields and signing
- **contentAccessibility** (boolean) - Optional - Allow copying text for accessibility
- **documentAssembly** (boolean) - Optional - Allow document assembly
```

--------------------------------

### Add Various Annotations to PDF

Source: https://pdfkit.org/docs/annotations.html

Demonstrates adding multiple annotation types including links, underlines, highlights, spot colors, strikes, and notes. Remember that link annotations should be added last to ensure they are clickable.

```javascript
// Add the link text
doc.fontSize(25)
   .fillColor('blue')
   .text('This is a link!', 20, 0);

// Measure the text
const width = doc.widthOfString('This is a link!');
const height = doc.currentLineHeight();

// Add the underline and link annotations
doc.underline(20, 0, width, height, {color: 'blue'})
   .link(20, 0, width, height, 'http://google.com/');

// Create the highlighted text
doc.moveDown()
   .fillColor('black')
   .highlight(20, doc.y, doc.widthOfString('This text is highlighted!'), height)
   .text('This text is highlighted!');

// Create text with a spot color
doc.addSpotColor('PANTONE185C', 0, 100, 78, 9)
doc.moveDown()
   .fillColor('PANTONE185C')
   .text('This text uses spot color!');

// Create the crossed out text
doc.moveDown()
   .strike(20, doc.y, doc.widthOfString('STRIKE!'), height)
   .text('STRIKE!');

// Create note
doc.note(10, 30, 30, 30, "Text of note");

// Create note with custom options
doc.note(10, 80, 30, 30, "Text of custom note", {Name: 'Key', color: 'red'});

// Adding go to as annotation
doc.goTo(20, doc.y, 10, 20, 'LINK', {});
```

--------------------------------

### Create a hierarchical form structure

Source: https://pdfkit.org/docs/forms.html

Demonstrates organizing form fields into a parent-child hierarchy and adding annotations to those fields.

```javascript
doc.font('Helvetica'); // establishes the default font doc.initForm();
let rootField = doc.formField('rootField'); let child1Field = doc.formField('child1Field', { parent: rootField }); let child2Field = doc.formField('child2Field', { parent: rootField });
// Add text form annotation 'rootField.child1Field.leaf1' doc.formText('leaf1', 10, 10, 200, 40, { parent: child1Field, multiline: true }); // Add text form annotation 'rootField.child1Field.leaf2' doc.formText('leaf2', 10, 60, 200, 40, { parent: child1Field, multiline: true }); // Add text form annotation 'rootField.child2Field.leaf1' doc.formText('leaf1', 10, 110, 200, 80, { parent: child2Field, multiline: true });
// Add push button form annotation 'btn1' var opts = { backgroundColor: 'yellow', label: 'Test Button' }; doc.formPushButton('btn1', 10, 200, 100, 30, opts);
```

--------------------------------

### Creating Complex Nested Structures

Source: https://pdfkit.org/docs/accessibility.html

Shows how to define nested structure elements and add them to the document's structure.

```javascript
// Create nested structure elements
const section1 = doc.struct('Sect', [
    doc.struct('P', [
        someTextStructureContent,
        doc.struct('Link', someLinkStructureContent),
        moreTextStructureContent
    ])
]);
const section2 = doc.struct('Sect', secondSectionStructureContent);

// Add them to the document's structure
doc.addStructure(section1).addStructure(section2);
```

--------------------------------

### Marking Structure Content and Artifacts

Source: https://pdfkit.org/docs/accessibility.html

Demonstrates how to mark content as artifacts or structure elements, noting that these are mutually exclusive and will automatically end previous markings.

```javascript
// Mark multiple paragraphs without needing to close them
doc.markContent('Artifact', { type: "Layout" });
doc.rect(x1, y1, w1, h1);
const myStructContent = doc.markStructureContent('P');
doc.text('Hello, world! ');
doc.markContent('Artifact', { type: "Layout" });
doc.rect(x2, y2, w2, h1);
const myStructContent = doc.markStructureContent('P');
doc.markContent('Span');
doc.text('Bonjour, tout le monde! ');
doc.markContent('Artifact', { type: "Layout" });
doc.rect(x3, y3, w3, h1);
const myStructContent = doc.markStructureContent('P');
doc.text('Hello again! ');
```

--------------------------------

### Table Positioning

Source: https://pdfkit.org/docs/table.html

Demonstrates how tables are positioned within the document flow, and how subsequent content follows.

```APIDOC
## Table Positioning
Internally, PDFKit keeps track of the current X and Y position of table as it is added to the document. This way, any calls to `text` or `table` will be placed below the table row.
```javascript
doc
    .text('before')
    .table({
        data: [
            ['Column 1', 'Column 2', 'Column 3'],
            ['One value goes here', 'Another one here', 'OK?']
        ]
    })
    .text('after')
```
```

--------------------------------

### Common Form Annotation Options

Source: https://pdfkit.org/docs/forms.html

Configuration options applicable to most form annotation types.

```APIDOC
## Common Options

### Description
These options can be used with most form annotation types to control their behavior and appearance.

### Options
- **required** (_boolean_): If true, the field must have a value upon form submission.
- **noExport** (_boolean_): If true, the field's value will not be included in form submissions.
- **readOnly** (_boolean_): If true, the user cannot change the field's value, and it will not respond to clicks. Useful for computed fields.
- **value** (_number|string_): The initial or current value of the field.
- **defaultValue** (_number|string_): The value the field reverts to when a reset-form action is executed.
- **backgroundColor** (_color_): Sets the background color of the field. Accepts RGB arrays, hex colors, or CSS color names.
- **borderColor** (_color_): Sets the border color of the field. Accepts RGB arrays, hex colors, or CSS color names.

### Color Format
Colors can be specified as:
- An array of RGB values (e.g., `[255, 0, 0]` for red).
- A hex color string (e.g., `'#FF0000'` for red).
- A named CSS color value (e.g., `'red'`).
```

--------------------------------

### Document Metadata Configuration

Source: https://pdfkit.org/docs/getting_started.html

Configure document metadata by adding properties to the doc.info object or passing an info object during document creation.

```APIDOC
## Document Metadata

### Description
Set metadata properties for the PDF document. Properties must have their first letter capitalized.

### Request Body
- **Title** (string) - Optional - The title of the document
- **Author** (string) - Optional - The name of the author
- **Subject** (string) - Optional - The subject of the document
- **Keywords** (string) - Optional - Keywords associated with the document
- **CreationDate** (date) - Optional - The date the document was created
- **ModDate** (date) - Optional - The date the document was last modified
```

--------------------------------

### Buffer pages for post-processing

Source: https://pdfkit.org/docs/getting_started.html

Enable page buffering to allow switching back to previous pages for tasks like adding page numbers.

```javascript
// create a document, and enable bufferPages mode
let i;
let end;
const doc = new PDFDocument({
  bufferPages: true});

// add some content...
doc.addPage();
// ...
doc.addPage();

// see the range of buffered pages
const range = doc.bufferedPageRange(); // => { start: 0, count: 2 }

for (i = range.start, end = range.start + range.count, range.start <= end; i < end; i++) {
  doc.switchToPage(i);
  doc.text(`Page ${i + 1} of ${range.count}`);
}

// manually flush pages that have been buffered
doc.flushPages();

// or, if you are at the end of the document anyway,
// doc.end() will call it for you automatically.
doc.end();
```

--------------------------------

### Cell Options

Source: https://pdfkit.org/docs/table.html

Lists and describes the available options for configuring individual table cells.

```APIDOC
## Cell options
  * `text` - The value, will be cast to a string (`null` and `undefined` are not rendered but the cell is still outlined)
  * `rowSpan` - How many rows this cell covers, follows the same logic as HTML `rowspan`
  * `colSpan` - How many columns this cell covers, follows the same logic as HTML `colspan`
  * `padding` - The padding for the cell (default `0.25em`)
  * `border` - The border for the cell (default `1pt`)
  * `borderColor` - The border colors for the cell (default `black`)
  * `font` - Font options for the cell
  * `backgroundColor` - Set the background color of the cell
  * `align` - The alignment of the cell text (default `{x: 'left', y: 'top'}`)
  * `textStroke` - The text stroke (default `0`)
  * `textStrokeColor` - Sets the text stroke color of the cells text (default `black`)
  * `textColor` - Sets the text color of the cells text (default `black`)
  * `type` - Sets the cell type (for accessibility) (default `TD`)
  * `textOptions` - Sets any text options you wish to provide (such as rotation)
  * `debug` - Whether to show the debug lines for the cell (default `false`)
```

--------------------------------

### Create a Push Button

Source: https://pdfkit.org/docs/forms.html

Adds a push button with custom background color and label.

```javascript
var opts = {   backgroundColor: 'yellow',   label: 'Test Button' }; doc.formPushButton('btn1', 10, 200, 100, 30, opts); 
```

--------------------------------

### Limitations and Testing

Source: https://pdfkit.org/docs/forms.html

Recommends testing PDF form documents across various platforms and viewers to ensure compatibility.

```APIDOC
## Limitations
It is recommended that you test your PDF form documents across all platforms and viewers that you wish to support.
```

--------------------------------

### Column Options

Source: https://pdfkit.org/docs/table.html

Lists and describes the options available for configuring table columns, extending cell options.

```APIDOC
## Column options
Extends the cell options above with:
  * `width` - The width of the column (default `*`)
  * `minWidth` - The minimum width of the column (default `0`)
  * `maxWidth` - The maximum width of the column (default `Infinity`)
```

--------------------------------

### Set default document font

Source: https://pdfkit.org/docs/getting_started.html

Configure the global font for the document during initialization.

```javascript
// use Courier font by default
const doc = new PDFDocument({font: 'Courier'});
```

--------------------------------

### Listen for page added events

Source: https://pdfkit.org/docs/getting_started.html

Execute code automatically whenever a new page is created.

```javascript
doc.on('pageAdded', () => doc.text("Page Title"));
```

--------------------------------

### Shortcut for Marked Content Elements

Source: https://pdfkit.org/docs/accessibility.html

Provides a shorthand for creating structure elements that contain only marked content using a closure.

```javascript
doc.addStructure(doc.struct('P', () => {
    doc.text('Hello, world! ');
}));
```

```javascript
const myStruct = doc.struct('P');
doc.addStructure(myStruct);
const myStructContent = doc.markStructureContent('P');
doc.text('Hello, world! ');
doc.endMarkedContent();
myStruct.add(myStructContent);
myStruct.end();
```

--------------------------------

### Save and Restore Graphics State in PDFKit

Source: https://pdfkit.org/docs/vector.html

Manage the graphics state using `save` and `restore` methods. `save` pushes the current state (styles and transformations) onto a stack, and `restore` applies the last saved state.

```javascript
// Example usage (conceptual, no direct code snippet provided in source)
// doc.save();
// doc.fillColor('blue');
// doc.restore();
```

--------------------------------

### Pipe PDF output to streams

Source: https://pdfkit.org/docs/getting_started.html

Direct the document output to a file system stream or an HTTP response object before finalizing.

```javascript
doc.pipe(fs.createWriteStream('/path/to/file.pdf')); // write to PDF
doc.pipe(res);                                       // HTTP response

// add stuff to PDF here using methods described below...

// finalize the PDF and end the stream
doc.end();
```

--------------------------------

### Create a Combo Box

Source: https://pdfkit.org/docs/forms.html

Adds a combo box field with a predefined list of selectable options.

```javascript
opts = {   select: ['', 'github', 'bitbucket', 'gitlab'],   value: '',   defaultValue: '',   align: 'left' }; doc.formCombo('ch1', 10, y, 100, 20, opts); 
```

--------------------------------

### Apply Tiling Pattern Fill and Stroke

Source: https://pdfkit.org/examples/browserify/browser.html

Defines and applies a custom tiling pattern for both fill and stroke operations. The pattern is defined using a specific syntax and can be combined with colors.

```javascript
// stroke & fill uncolored tiling pattern
var stripe45d = doc.pattern(
[1, 1, 4, 4],
3,
3,
'1 w 0 1 m 4 5 l s 2 0 m 5 3 l s'
);
doc.circle(280, 350, 50).fill([stripe45d, 'blue']);
doc
.rect(380, 300, 100, 100)
.fillColor('lime')
.strokeColor([stripe45d, 'orange'])
.lineWidth(5)
.fillAndStroke();
doc.restore();
```