多个帆布我想在一个HTML页面4画布上显示他们每个人对应一个pdf文件的页面。 我成功地在1个画布中显示1页,但是当我想显示4时它不起作用:没有显示任何页面。使用与pdf.js
我在做什么错了?
编辑: 我试图解决的承诺的问题(我编辑的代码),但现在我得到了另一个错误:Error: Invalid page request pdf.js:2687:31
这里是对应的代码(2697是返回的路线):
getPage: function WorkerTransport_getPage(pageNumber, capability) {
if (pageNumber <= 0 || pageNumber > this.numPages ||
(pageNumber|0) !== pageNumber) {
return Promise.reject(new Error('Invalid page request'));
}
这里是我的代码:
HTML文件:
<html>
<head>
<meta charset="utf-8"/>
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0">
<meta name="description" content="PDF Viewer"/>
<title>My page</title>
</head>
<body>
<body>
<canvas id="canvas1" width="300" height="300"></canvas>
<canvas id="canvas2" width="300" height="300"></canvas>
<canvas id="canvas3" width="300" height="300"></canvas>
<canvas id="canvas4" width="300" height="300"></canvas>
<script src="/assets/js/pdf.js"></script>
<script src="/assets/js/pdf.worker.js"></script>
<script src="/assets/js/pdf.latex.main.js"></script>
</body>
</html>
JA vascript文件(pdf.latex.main.js):
PDFJS.disableStream = true;
var pdfFile;
PDFJS.getDocument('/assets/pdf/tempPDF.pdf').then(function (pdf) {
pdfFile = pdf;
for(var i = 1; i < 4; i++) {
var canvas = document.getElementById('canvas'+i);
var context = canvas.getContext('2d');
PDFJS.disableStream = true;
openPage(pdf, i, context);
}
});
function openPage(pdfFile, pageNumber, context) {
var scale = 5;
pdfFile.getPage(pageNumber).then(function (page) {
viewport = page.getViewport(scale);
// reference canvas via context
var canvas = context.canvas;
canvas.width = viewport.width;
canvas.height = viewport.height;
canvas.style.width = "100%";
canvas.style.height = "100%";
wrapper.style.width = Math.floor(viewport.width/scale) + 'pt';
wrapper.style.height = Math.floor(viewport.height/scale) + 'pt';
var renderContext = {
canvasContext: context
, viewport: viewport
};
page.render(renderContext);
});
}
请介绍 “不工作”以更详细的方式。 – Thevs
看看https://stackoverflow.com/a/44548566/1765767帮助 – async5