我想知道是否有办法使用input type="file"
选择pdf文件并使用PDFJS
答案 0 :(得分:23)
您应该能够使用FileReader将文件对象的内容作为类型化数组获取,PDFJS接受(http://mozilla.github.io/pdf.js/api/draft/PDFJS.html)
//Step 1: Get the file from the input element
inputElement.onchange = function(event) {
var file = event.target.files[0];
//Step 2: Read the file using file reader
var fileReader = new FileReader();
fileReader.onload = function() {
//Step 4:turn array buffer into typed array
var typedarray = new Uint8Array(this.result);
//Step 5:PDFJS should be able to read this
PDFJS.getDocument(typedarray).then(function(pdf) {
// do stuff
});
};
//Step 3:Read the file as ArrayBuffer
fileReader.readAsArrayBuffer(file);
}
答案 1 :(得分:2)
我认为我已经设法用新的API解决了新问题。如this GitHub issue中所述,getDocument
函数现在已添加了一个promise
。
简而言之:
PDFJS.getDocument(typedarray).then(function(pdf) {
// The document is loaded here...
});
成为这个:
const loadingTask = pdfjsLib.getDocument(typedarray);
loadingTask.promise.then(pdf => {
// The document is loaded here...
});
使旧的答案适应新的api以符合赏金的要求,结果如下:
//Step 1: Get the file from the input element
inputElement.onchange = function(event) {
//It is important that you use the file and not the filepath (The file path won't work because of security issues)
var file = event.target.files[0];
var fileReader = new FileReader();
fileReader.onload = function() {
var typedarray = new Uint8Array(this.result);
//replaced the old function with the new api
const loadingTask = pdfjsLib.getDocument(typedarray);
loadingTask.promise.then(pdf => {
// The document is loaded here...
});
};
//Step 3:Read the file as ArrayBuffer
fileReader.readAsArrayBuffer(file);
}
我在下面创建了一个带有以下源代码正式发行版的示例,以表明它正在工作。
/*Offical release of the pdfjs worker*/
pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/2.5.207/pdf.worker.js';
document.getElementById('file').onchange = function(event) {
var file = event.target.files[0];
var fileReader = new FileReader();
fileReader.onload = function() {
var typedarray = new Uint8Array(this.result);
console.log(typedarray);
const loadingTask = pdfjsLib.getDocument(typedarray);
loadingTask.promise.then(pdf => {
// The document is loaded here...
//This below is just for demonstration purposes showing that it works with the moderen api
pdf.getPage(1).then(function(page) {
console.log('Page loaded');
var scale = 1.5;
var viewport = page.getViewport({
scale: scale
});
var canvas = document.getElementById('pdfCanvas');
var context = canvas.getContext('2d');
canvas.height = viewport.height;
canvas.width = viewport.width;
// Render PDF page into canvas context
var renderContext = {
canvasContext: context,
viewport: viewport
};
var renderTask = page.render(renderContext);
renderTask.promise.then(function() {
console.log('Page rendered');
});
});
//end of example code
});
}
fileReader.readAsArrayBuffer(file);
}
<html>
<head>
<!-- The offical release-->
<script src="https://cdnjs.cloudflare.com/ajax/libs/pdf.js/2.5.207/pdf.js"> </script>
</head>
<body>
<input type="file" id="file">
<h2>Rendered pdf:</h2>
<canvas id="pdfCanvas" width="300" height="300"></canvas>
</body>
</html>
希望这会有所帮助!如果没有,请发表评论。
这可能在jsFiddle中不起作用。