最近有一個需求,須要在釘釘微應用PC端應用上展現pdf文件,無奈釘釘的的webview不支持embed
標籤,故爲了兼容只能使用圖片來展現pdf文件
項目是用react寫的,ui爲antd,腳手架umi,npm上找了幾個pdf轉圖片的react庫,例如react-pdf,瀏覽器展現沒有問題,可是在釘釘上遇到了javascript
The browser/environment lacks native support for critical functionality used by the PDF.js library (e.g. 'ReadableStream' and/or 'Promise.allSettled'); please use an ES5-compatible build instead.
該錯誤,點擊這裏查看相關內容。後改用了pdfjd-distjava
import React, { useState, useEffect, useRef } from 'react'; import { Spin, Pagination } from 'antd'; var pdfjsLib = require('pdfjs-dist/es5/build/pdf.js'); import 'pdfjs-dist/es5/build/pdf.worker.entry'; interface PdfViewerProps { url: string; } const PdfViewer = ({ url }: PdfViewerProps) => { const [pageNumbers, setPageNumbers] = useState(0); const [currentPage, setCurrentPage] = useState(1); const [loading, setLoading] = useState(true); const [rendering, setRendering] = useState(false); const pdfRef: any = useRef(null); function renderPdf(pdfFile: any) { let canvas: any = document.getElementById('pdf'); let canvasContext = canvas.getContext('2d'); pdfFile.getPage(currentPage).then((page: any) => { //逐頁解析PDF var viewport = page.getViewport({ scale: 5 }); // 頁面縮放比例,值越大越清晰 canvas.height = viewport.height; canvas.width = viewport.width; canvasContext.clearRect(0, 0, canvas.width, canvas.height); var renderContext = { canvasContext: canvasContext, viewport: viewport, rotate: 90, }; setRendering(true); page.render(renderContext).promise.finally(() => { setRendering(false); }); //渲染生成 }); } useEffect(() => { let loadingTask = pdfjsLib.getDocument(url); loadingTask.promise .then((pdf: any) => { // console.log(pdf.numPages); pdfRef.current = pdf; setPageNumbers(pdf.numPages); renderPdf(pdf); }) .catch((error: any) => { console.log(error); }) .finally(() => { setLoading(false); }); }, []); useEffect(() => { if (pdfRef.current) { window.scrollTo({ top: 0 }); renderPdf(pdfRef.current); } }, [currentPage]); return ( <Spin spinning={loading || rendering}> <div> <canvas id="pdf" style={{ width: '100%' }} /> {!loading && ( <Pagination style={{ textAlign: 'center', marginTop: 15 }} current={currentPage} total={pageNumbers} pageSize={1} onChange={value => setCurrentPage(value)} /> )} </div> </Spin> ); }; export default PdfViewer;
<PdfViewer url="temp.pdf" />