vue-pdf打印出现方字块乱码问题

问题：

第一种：

第二种方法：

好吧，改的真麻烦直接给改完后的代码：

最终效果：

总结：

问题：

今天分享vue-pdf预览显示没有问题，但是打印时出现乱码问题。话不多说先上乱码图。今天主要是分享给大家两种方法。亲测有效!!!!!!!!

第一：在你使用vue-pdf的组件中使用<iframe>标签,如果对iframe不熟悉也没有关系，你就知道iframe 元素会创建包含另外一个文档的内联框架就OK了。

第一种：

把iframe标签放入组件中，这里我是放在pdf标签下方的

<iframe id="printIframe" :src="src" frameborder="0" style="display:none"></iframe>

iframe里面的' :src '是其本身的属性，"src"这个src是一个字符串，也是我PDF文件的地址，我这里是写了一个固定地址是放在我们component文件中的。直接在data里面的return中声明一个src变量并对它赋值就可以了
然后在你绑定的打印按钮的方法中直接使用

document.getElementById('printIframe').contentWindow.print();

替代原来的方法 //this.$refs.mypdf.print()就可以了

代码如下：

<template>

<el-dialog

title="合同内容"

:visible.sync="dialogVisible"

width="70%"

:before-close="handleClose">



<el-button @click="num--" v-if="num>=1">上一页</el-button>

<el-button @click="num++" v-if="num<=pageCount">下一页</el-button>

<el-button @click="print">打印合同</el-button>

{{currentPage}}/{{pageCount}}

<pdf

:src=src :page="num"

@num-pages="pageCount = $event"

@page-loaded="currentPage=$event"

style="display:inline-block;width:500px"

ref="mypdf"

></pdf>

<iframe id="printIframe" :src="src" frameborder="0" style="display:none"></iframe>

<span slot="footer" class="dialog-footer">

<el-button @click="dialogVisible = false">取消</el-button>

<el-button type="primary" @click="dialogVisible = false">确定</el-button>

</span>

</el-dialog>

</template>

<script>

import pdf from 'vue-pdf'

export default {

name: 'VuePdf',

components: {pdf},

data () {

return {

dialogVisible: false,

currentPage:0,

pageCount:0,

num:1,

src:'./test.pdf',

}

},

methods:{

print(){

//打印合同的方法

//this.$refs.mypdf.print()

document.getElementById('printIframe').contentWindow.print();

},

handleClose(done) {

this.$confirm('确认关闭？')

.then(()=> {

done();

})

.catch(()=> {});

}

}

}

</script>

<style>

</style>

第二种方法：

第二种方法是改变原码的方式，在node_modules下的vue-pdf下的src下的pdfjsWrapper.js中。

乱码问题是因为我们安装vue-pdf的版本问题，它的这个源码因为版本更新已经改变了，下面这个地址详细的介绍了源码的改变。红色区域的'-'号表明是已经删除了的，绿色区域的加号是新加的。

使用方法就是你把红色区域的注释掉，并加上绿色区域的！！！！

github网址：https://github.com/FranckFreiburger/vue-pdf/pull/130/commits/253f6186ff0676abf9277786087dda8d95dd8ea7

部分内容：

需要注意的是里面的行数会有一些区别，可以Ctrl+H搜索关键字定位

下卖以我的代码行数为例：

首先找到上图中显示的78行位置，我是在91行：注释掉它，并且在下方加入绿色的两行！~~~~~好了就是按照这样改就好啦。

好吧，改的真麻烦直接给改完后的代码：

import { PDFLinkService } from 'pdfjs-dist/es5/web/pdf_viewer';var pendingOperation = Promise.resolve();export default function(PDFJS) {function isPDFDocumentLoadingTask(obj) {return typeof(obj) === 'object' && obj !== null && obj.__PDFDocumentLoadingTask === true;// or: return obj.constructor.name === 'PDFDocumentLoadingTask';}function createLoadingTask(src, options) {var source;if ( typeof(src) === 'string' )source = { url: src };else if ( src instanceof Uint8Array )source = { data: src };else if ( typeof(src) === 'object' && src !== null )source = Object.assign({}, src);elsethrow new TypeError('invalid src type');// source.verbosity = PDFJS.VerbosityLevel.INFOS;// source.pdfBug = true;// source.stopAtErrors = true;if ( options && options.withCredentials )source.withCredentials = options.withCredentials;var loadingTask = PDFJS.getDocument(source);loadingTask.__PDFDocumentLoadingTask = true; // since PDFDocumentLoadingTask is not publicif ( options && options.onPassword )loadingTask.onPassword = options.onPassword;if ( options && options.onProgress )loadingTask.onProgress = options.onProgress;return loadingTask;}function PDFJSWrapper(canvasElt, annotationLayerElt, emitEvent) {var pdfDoc = null;var pdfPage = null;var pdfRender = null;var canceling = false;canvasElt.getContext('2d').save();function clearCanvas() {canvasElt.getContext('2d').clearRect(0, 0, canvasElt.width, canvasElt.height);}function clearAnnotations() {while ( annotationLayerElt.firstChild )annotationLayerElt.removeChild(annotationLayerElt.firstChild);}this.destroy = function() {if ( pdfDoc === null )return;// Aborts all network requests and destroys worker.pendingOperation = pdfDoc.destroy();pdfDoc = null;}this.getResolutionScale = function() {return canvasElt.offsetWidth / canvasElt.width;}this.printPage = function(dpi, pageNumberOnly) {if ( pdfPage === null )return;// 1in == 72pt// 1in == 96pxvar PRINT_RESOLUTION = dpi === undefined ? 150 : dpi;var PRINT_UNITS = PRINT_RESOLUTION / 72.0;var CSS_UNITS = 96.0 / 72.0;var printContainerElement = document.createElement('div');printContainerElement.setAttribute('id', 'print-container')function removePrintContainer() {printContainerElement.parentNode.removeChild(printContainerElement);}new Promise(function(resolve, reject) {printContainerElement.frameBorder = '0';printContainerElement.scrolling = 'no';printContainerElement.width = '0px;'printContainerElement.height = '0px;'printContainerElement.style.cssText = 'position: absolute; top: 0; left: 0';window.document.body.appendChild(printContainerElement);resolve(window)}).then(function(win) {win.document.title = '';return pdfDoc.getPage(1).then(function(page) {var viewport = page.getViewport({ scale: 1 });printContainerElement.appendChild(win.document.createElement('style')).textContent ='@supports ((size:A4) and (size:1pt 1pt)) {' +'@page { margin: 1pt; size: ' + ((viewport.width * PRINT_UNITS) / CSS_UNITS) + 'pt ' + ((viewport.height * PRINT_UNITS) / CSS_UNITS) + 'pt; }' +'}' +'@media print {' +'body { margin: 0 }' +'#print-canvas { page-break-before: avoid; page-break-after: always; page-break-inside: avoid; display: block }' +'body > *:not(#print-container) { display: none; }' +'}'+'@media screen {' +'body { margin: 0 }' +'}'return win;})}).then(function(win) {var allPages = [];for ( var pageNumber = 1; pageNumber <= pdfDoc.numPages; ++pageNumber ) {if ( pageNumberOnly !== undefined && pageNumberOnly.indexOf(pageNumber) === -1 )continue;allPages.push(pdfDoc.getPage(pageNumber).then(function(page) {var viewport = page.getViewport({ scale: 1 });var printCanvasElt = printContainerElement.appendChild(win.document.createElement('canvas'));printCanvasElt.setAttribute('id', 'print-canvas')printCanvasElt.width = (viewport.width * PRINT_UNITS);printCanvasElt.height = (viewport.height * PRINT_UNITS);return page.render({canvasContext: printCanvasElt.getContext('2d'),transform: [ // Additional transform, applied just before viewport transform.PRINT_UNITS, 0, 0,PRINT_UNITS, 0, 0],viewport: viewport,intent: 'print'}).promise;}));}Promise.all(allPages).then(function() {win.focus(); // Required for IEif (win.document.queryCommandSupported('print')) {win.document.execCommand('print', false, null);} else {win.print();}removePrintContainer();}).catch(function(err) {removePrintContainer();emitEvent('error', err);})})}this.renderPage = function(rotate) {if ( pdfRender !== null ) {if ( canceling )return;canceling = true;pdfRender.cancel().catch(function(err) {emitEvent('error', err);});return;}if ( pdfPage === null )return;var pageRotate = (pdfPage.rotate === undefined ? 0 : pdfPage.rotate) + (rotate === undefined ? 0 : rotate);var scale = canvasElt.offsetWidth / pdfPage.getViewport({ scale: 1 }).width * (window.devicePixelRatio || 1);var viewport = pdfPage.getViewport({ scale: scale, rotation:pageRotate });emitEvent('page-size', viewport.width, viewport.height, scale);canvasElt.width = viewport.width;canvasElt.height = viewport.height;pdfRender = pdfPage.render({canvasContext: canvasElt.getContext('2d'),viewport: viewport});annotationLayerElt.style.visibility = 'hidden';clearAnnotations();var viewer = {scrollPageIntoView: function(params) {emitEvent('link-clicked', params.pageNumber)},};var linkService = new PDFLinkService();linkService.setDocument(pdfDoc);linkService.setViewer(viewer);pendingOperation = pendingOperation.then(function() {var getAnnotationsOperation =pdfPage.getAnnotations({ intent: 'display' }).then(function(annotations) {PDFJS.AnnotationLayer.render({viewport: viewport.clone({ dontFlip: true }),div: annotationLayerElt,annotations: annotations,page: pdfPage,linkService: linkService,renderInteractiveForms: false});});var pdfRenderOperation =pdfRender.promise.then(function() {annotationLayerElt.style.visibility = '';canceling = false;pdfRender = null;}).catch(function(err) {pdfRender = null;if ( err instanceof PDFJS.RenderingCancelledException ) {canceling = false;this.renderPage(rotate);return;}emitEvent('error', err);}.bind(this))return Promise.all([getAnnotationsOperation, pdfRenderOperation]);}.bind(this));}this.forEachPage = function(pageCallback) {var numPages = pdfDoc.numPages;(function next(pageNum) {pdfDoc.getPage(pageNum).then(pageCallback).then(function() {if ( ++pageNum <= numPages )next(pageNum);})})(1);}this.loadPage = function(pageNumber, rotate) {pdfPage = null;if ( pdfDoc === null )return;pendingOperation = pendingOperation.then(function() {return pdfDoc.getPage(pageNumber);}).then(function(page) {pdfPage = page;this.renderPage(rotate);emitEvent('page-loaded', page.pageNumber);}.bind(this)).catch(function(err) {clearCanvas();clearAnnotations();emitEvent('error', err);});}this.loadDocument = function(src) {pdfDoc = null;pdfPage = null;emitEvent('num-pages', undefined);if ( !src ) {canvasElt.removeAttribute('width');canvasElt.removeAttribute('height');clearAnnotations();return;}// wait for pending operation endspendingOperation = pendingOperation.then(function() {var loadingTask;if ( isPDFDocumentLoadingTask(src) ) {if ( src.destroyed ) {emitEvent('error', new Error('loadingTask has been destroyed'));return}loadingTask = src;} else {loadingTask = createLoadingTask(src, {onPassword: function(updatePassword, reason) {var reasonStr;switch (reason) {case PDFJS.PasswordResponses.NEED_PASSWORD:reasonStr = 'NEED_PASSWORD';break;case PDFJS.PasswordResponses.INCORRECT_PASSWORD:reasonStr = 'INCORRECT_PASSWORD';break;}emitEvent('password', updatePassword, reasonStr);},onProgress: function(status) {var ratio = status.loaded / status.total;emitEvent('progress', Math.min(ratio, 1));}});}return loadingTask.promise;}).then(function(pdf) {pdfDoc = pdf;emitEvent('num-pages', pdf.numPages);emitEvent('loaded');}).catch(function(err) {clearCanvas();clearAnnotations();emitEvent('error', err);})}annotationLayerElt.style.transformOrigin = '0 0';}return {createLoadingTask: createLoadingTask,PDFJSWrapper: PDFJSWrapper,}
}

最终效果：

总结：

第一种看起来真的很简单快捷，但是第二种可以了解为什么会出现乱码问题，看看哪种方法适合你吧，如果有用欢迎点赞评论收藏一波哟