vue2.0全局组件之pdf详解

目的：像elementUI那样注册全局组件 预览pdf文件

技术支持：使用火狐的pdf.js

准备：新建一个CPdf.vue文件，把火狐demo里面的build里面的pdf.js下载来,并且依赖了elementUI开发的其实就是用了<el-button>

编写：

template

<template> <div> <div> <div> <el-button @click="prev">上一页</el-button> <el-button @click="next">下一页</el-button> &nbsp; &nbsp; <span>Page: <span v-text="page_num"></span> / <span v-text="page_count"></span></span> &nbsp; &nbsp; <el-button @click="addscale" icon="plus"></el-button> <el-button @click="minus" icon="minus"></el-button> <el-button @click="closepdf">关闭</el-button> </div> <canvas></canvas> </div> </div> </template>

js

import PDFJS from '../../../static/pdf/pdf.js' import { mapActions, mapGetters } from 'vuex'; export default { name: 'c-pdf', props: ['pdfurl'], data() { return { pdfDoc: null, //pdfjs 生成的对象 pageNum: 1,// pageRendering: false, pageNumPending: null, scale: 1.2,//放大倍数 page_num: 0,//当前页数 page_count: 0,//总页数 maxscale: 2,//最大放大倍数 minscale: 0.8//最小放大倍数 } }, methods: { renderPage(num) { //渲染pdf let vm = this this.pageRendering = true; let canvas = document.getElementById('the-canvas') // Using promise to fetch the page this.pdfDoc.getPage(num).then(function(page) { var viewport = page.getViewport(vm.scale); //alert(vm.canvas.height) canvas.height = viewport.height; canvas.width = viewport.width; // Render PDF page into canvas context var renderContext = { canvasContext: vm.ctx, viewport: viewport }; var renderTask = page.render(renderContext); // Wait for rendering to finish renderTask.promise.then(function() { vm.pageRendering = false; if(vm.pageNumPending !== null) { // New page rendering is pending vm.renderPage(vm.pageNumPending); vm.pageNumPending = null; } }); }); vm.page_num = vm.pageNum; }, addscale() {//放大 if(this.scale >= this.maxscale) { return } this.scale += 0.1; this.queueRenderPage(this.pageNum) }, minus() {//缩小 if(this.scale <= this.minscale) { return } this.scale -= 0.1; this.queueRenderPage(this.pageNum) }, prev() {//上一页 let vm = this if(vm.pageNum <= 1) { return; } vm.pageNum--; vm.queueRenderPage(vm.pageNum); }, next() {//下一页 let vm = this if(vm.pageNum >= vm.page_count) { return; } vm.pageNum++; vm.queueRenderPage(vm.pageNum); }, closepdf() {//关闭PDF this.$emit('closepdf') }, queueRenderPage(num) { if(this.pageRendering) { this.pageNumPending = num; } else { this.renderPage(num); } } }, computed: { ctx() { let id = document.getElementById('the-canvas') return id.getContext('2d'); } }, mounted() { let vm = this PDFJS.getDocument(vm.pdfurl).then(function(pdfDoc_) { //初始化pdf vm.pdfDoc = pdfDoc_; vm.page_count = vm.pdfDoc.numPages vm.renderPage(vm.pageNum); }); } }

style less

.cpdf { position: fixed; top: 0; left: 0; background-color: rgba(0, 0, 0, .5); width: 100%; height: 100%; z-index: 99999; display: flex; justify-content: center; align-items: center; .center { text-align: center; height: 100%; overflow: auto; padding-top: 20px; .contor { margin-bottom: 10px; } } }

注册到全局：在main.js 引入CPdf.vue

Vue.component(CPdf.name, CPdf)

使用：在想预览pdf文件的组件里面

<c-pdf @closepdf="closepdf" v-show="isshowpdf" :pdfurl="testpdfurl"></c-pdf>

data() { return { isshowpdf:false, testpdfurl:'//cdn.mozilla.net/pdfjs/tracemonkey.pdf' } }, methods: { closepdf(){ this.isshowpdf=false }, }

效果：

npm :有人关注 那么我就发到 npm 上。 地址 https://www.npmjs.com/package/vueshowpdf