pdf-engine发布 - 技术栈

介绍

pdf-engine内部使用pdfium编译的Webassembly二进制文件。

目前已支持功能:

解析XObject和Annotation对象
页面预览
编辑保存(创建Link)

安装

bash 复制代码

# yarn add @zouchengxin/pdf-engine
# pnpm install @zouchengxin/pdf-engine
npm install @zouchengxin/pdf-engine

使用

初始化

javascript 复制代码

import { PdfEngine } from '@zouchengxin/pdfium-engine';

const pdfEngine = new PdfEngine();
// API_KEY not provided, validity period until 2026-01-01, You can adjust the system time for testing.
// Or contact the developer to obtain the API key.
await pdfEngine.init(API_KEY);

解析

javascript 复制代码

// Load PDF documents, parameter Uint8Array
const pdfDoc = pdfEngine.loadPdf(data);
// Get the number of pages
const count = pdfDoc.getPageCount();
// Retrieves PDF metadata.
// returning the fields Title, Author, Subject, Keywords, Creator, Producer, CreationDate, and ModDate.
const meta = pdfDoc.getMetaData();
console.log('Page Count:', count);
console.log('Pdf Meta:', meta);
pdfPages.value = [];
for (let i = 0; i < count; i++) {
  // Obtain the page proxy object and perform operations such as parsing and editing.
  const page = pdfDoc.getPageProxy(i);
  // Get page width
  const width = page.getPageWidth();
  // Get page height
  const height = page.getPageHeight();
  // Retrieves all xobject objects on the page.
  // including those of type TEXT, PATH, IMAGE, SHADING, and FORM.
  const objs = page.getObjects();
  // Retrieves all annotation objects on the page.
  // including those of type TEXT, LINK, FREETEXT, LINE, SQUARE, CIRCLE, HIGHLIGHT, UNDERLINE, STAMP, INK etc.
  const annots = page.getAnnotions();
  console.log('Page Size:', width, height);
  console.log('Page Objects:', objs);
  console.log('Page Annotions:', annots);
}

渲染

javascript 复制代码

// Retrieve the bitmap after page rendering; render only the xobject object, excluding annotations.
// Return value: ImageData object
const data = page.getBitmap();
// Retrieve page thumbnail; return empty if not stored.
// Return value: ImageData object
const data = page.getThumbnail();

编辑

javascript 复制代码

// Create a link annotation.
// rect: a rectangular area.
// url: the redirect link.
page.createLinkAnno({
  rect: [100, 100, 160, 27],
  url: 'https://www.baidu.com',
});

// More features are under development.

// Save the PDF data and return a Uint8Array.
const uint8Arr = pdfDoc.savePdf();

注意

color: $r, g, b, a$ , 红绿蓝透明通道组成的数组。
rect: $x, y, w, h$ , 矩形区域左下角x/y坐标，w/h代表宽度高度。
坐标系: 页面左下角为原点，水平方向为x轴。
API_KEY: 联系开发者获取，或者修改系统时间至2026/01/01之前进行测试。