一、引入download.js
 
npm install downloadjs 
地址：https://www.npmjs.com/package/downloadjs
 
注意这个npm下载的这个download.js是有问题的，它能下载下来pdf文件，但是打不开这个pdf，在文章末尾的话，我会附上一个修改完的js。
 
<template>
  <div class="home">
    <!-- <HelloWorld @listener="show" ref="child" />
    <span>这是父组件的样式：</span> <span class="cssColor">color</span> -->
    <button @click="down">下载</button>
  </div>
</template>

<script>
// @ is an alias to /src
// 引入download.js
import download from "downloadjs";
export default {
  mounted() {
    // eslint-disable-next-line no-console
  },
  methods: {
    down() {
    /*我们只是需要这个地址放到这个里面就可以了*/
      download(
        "http://myweb-bucket.oss-cn-beijing.aliyuncs.com/2020/10/17/3fb95de68d8d45ebbf31d2c8f0724490新建 DOC 文档 (2).pdf"
      );
    }
  }
};
</script>
<style lang="scss" scoped>
/deep/ .cssColor {
  color: red;
}
</style>
 
// 你下载完后，需要替换一下你的这个js，这个才是可靠的
 
//download.js v4.21, by dandavis; 2008-2018. [MIT] see http://danml.com/download.html for tests/usage
// v1 landed a FF+Chrome compatible way of downloading strings to local un-named files, upgraded to use a hidden frame and optional mime
// v2 added named files via a[download], msSaveBlob, IE (10+) support, and window.URL support for larger+faster saves than dataURLs
// v3 added dataURL and Blob Input, bind-toggle arity, and legacy dataURL fallback was improved with force-download mime and base64 support. 3.1 improved safari handling.
// v4 adds AMD/UMD, commonJS, and plain browser support
// v4.1 adds url download capability via solo URL argument (same domain/CORS only)
// v4.2 adds semantic variable names, long (over 2MB) dataURL support, and hidden by default temp anchors
// https://github.com/rndme/download

/**
 * @typedef {Object} RequestData
 * @property {String} url - file url to download
 * @property {String} filename - custom filename to save
 * @property {String} data - data to save
 * @property {String} mimetype - custom file type
 */

(function (root, factory) {
	if (typeof define === 'function' && define.amd) {
		// AMD. Register as an anonymous module.
		define([], factory);
	} else if (typeof exports === 'object') {
		// Node. Does not work with strict CommonJS, but
		// only CommonJS-like environments that support module.exports,
		// like Node.
		module.exports = factory();
	} else {
		// Browser globals (root is window)
		root.download = factory();
  }
}(this, function () {
	var self = window, // this script is only for browsers anyway...
		defaultMime = "application/octet-stream", // this default mime also triggers iframe downloads
		blob,
		reader,
		anchor = document.createElement("a"),
		toString = function (a) { return String(a); },
		myBlob = (self.Blob || self.MozBlob || self.WebKitBlob || toString),
		myBlob= myBlob.call ? myBlob.bind(self) : Blob ;
	
	var processData = function(payload, fileName, mimeType){
		//go ahead and download dataURLs right away
		if(/^data:([\w+-]+\/[\w+.-]+)?[,;]/.test(payload)){
		
			if(payload.length > (1024*1024*1.999) && myBlob !== toString ){
				payload=dataUrlToBlob(payload);
				mimeType=payload.type || defaultMime;
			}else{			
				return navigator.msSaveBlob ?  // IE10 can't do a[download], only Blobs:
					navigator.msSaveBlob(dataUrlToBlob(payload), fileName) :
					saver(payload) ; // everyone else can save dataURLs un-processed
			}
			
		}else{//not data url, is it a string with special needs?
			if(/([\x80-\xff])/.test(payload)){			  
				var i=0, tempUiArr= new Uint8Array(payload.length), mx=tempUiArr.length;
				for(i;i<mx;++i) tempUiArr[i]= payload.charCodeAt(i);
			 	payload=new myBlob([tempUiArr], {type: mimeType});
			}		  
		}
		blob = payload instanceof myBlob ?
			payload :
			new myBlob([payload], {type: mimeType}) ;

		function dataUrlToBlob(strUrl) {
			var parts= strUrl.split(/[:;,]/),
			type= parts[1],
			indexDecoder = strUrl.indexOf("charset")>0 ? 3: 2,
			decoder= parts[indexDecoder] == "base64" ? atob : decodeURIComponent,
			binData= decoder( parts.pop() ),
			mx= binData.length,
			i= 0,
			uiArr= new Uint8Array(mx);

			for(i;i<mx;++i) uiArr[i]= binData.charCodeAt(i);

			return new myBlob([uiArr], {type: type});
		 }

		function saver(url, winMode){

			var _clickEvt = function(e) {
				e.stopPropagation();
				this.removeEventListener('click', _clickEvt);
			}
			if ('download' in anchor) { //html5 A[download]
				anchor.href = url;
				anchor.setAttribute("download", fileName);
				anchor.className = "download-js-link";
				anchor.innerHTML = "downloading...";
				anchor.style.display = "none";
				
				anchor.addEventListener('click', _clickEvt);
				document.body.appendChild(anchor);
				setTimeout(function() {
					anchor.click();
					document.body.removeChild(anchor);
					if(winMode===true){setTimeout(function(){ self.URL.revokeObjectURL(anchor.href);}, 250 );}
				}, 66);
				return true;
			}

			// handle non-a[download] safari as best we can:
			if(/(Version)\/(\d+)\.(\d+)(?:\.(\d+))?.*Safari\//.test(navigator.userAgent)) {
				if(/^data:/.test(url))	url="data:"+url.replace(/^data:([\w\/\-\+]+)/, defaultMime);
				if(!window.open(url)){ // popup blocked, offer direct download:
					if(confirm("Displaying New Document\n\nUse Save As... to download, then click back to return to this page.")){ location.href=url; }
				}
				return true;
			}

			//do iframe dataURL download (old ch+FF):
			var f = document.createElement("iframe");
			document.body.appendChild(f);

			if(!winMode && /^data:/.test(url)){ // force a mime that will download:
				url="data:"+url.replace(/^data:([\w\/\-\+]+)/, defaultMime);
			}
			f.src=url;
			setTimeout(function(){ document.body.removeChild(f); }, 333);

		}//end saver

		if (navigator.msSaveBlob) { // IE10+ : (has Blob, but not a[download] or URL)
			return navigator.msSaveBlob(blob, fileName);
		}

		if(self.URL){ // simple fast and modern way using Blob and URL:
			saver(self.URL.createObjectURL(blob), true);
		}else{
			// handle non-Blob()+non-URL browsers:
			if(typeof blob === "string" || blob.constructor===toString ){
				try{
					return saver( "data:" +  mimeType   + ";base64,"  +  self.btoa(blob)  );
				}catch(y){
					return saver( "data:" +  mimeType   + "," + encodeURIComponent(blob)  );
				}
			}

			// Blob but not URL support:
			reader=new FileReader();
			reader.onload=function(e){
				saver(this.result);
			};
			reader.readAsDataURL(blob);
		}
		return true;
	}

	/**
	 * data maybe String|{RequestData}|Blob, can download file with url given
	 * strFileName if provided, it only work with data saver
	 * strMimeType type of mime type, work like strFileName
	 */
	return function download(data, strFileName, strMimeType) {
		var mimeType = strMimeType || defaultMime,
			payload = data,
			url = !strFileName && !strMimeType && payload,
			fileName = strFileName || "";

	  
		if(String(this)==="true"){ //reverse arguments, allowing download.bind(true, "text/xml", "export.xml") to act as a callback
			payload=[payload, mimeType];
			mimeType=payload[0];
			payload=payload[1];
		}

		if (data instanceof Object) {
			if ('url' in data || 'data' in data) { // indicate this is new request type
				url = data['url'] || false;
				payload = data['data'];
				fileName = data['filename'] || fileName;
				mimeType = data['mimetype'] || mimeType;
			} else {
				return false;
			}
		}


		if (url && url.length < 2048) { // if no filename and no mime, assume a url was passed as the only argument
			fileName = fileName || url.split("/").pop().split("?")[0];
			anchor.href = url; // assign href prop to temp anchor
			if (anchor.href.match(/^https?:\/\//) != null) { // if the browser determines that it's a potentially valid url path:
				var ajax = new XMLHttpRequest();
				ajax.open("GET", url, true);
				ajax.responseType = 'blob';
				ajax.onload = function (e) {
					//   download(e.target.response, fileName, defaultMime);
					processData(e.target.response, fileName, defaultMime);
				};
				setTimeout(function () { ajax.send(); }, 0); // allows setting custom ajax headers using the return:
				return ajax;
			} // end if valid url?
		} else { // end if url?
			processData(payload, fileName, mimeType);
		}
	}; /* end download() */
}));
 
简单记录一下遇到的问题，如果有帮助到你记得三连。

首先安装依赖npm install html2canvas jspdf --save
封装方法：
 
// pdfMethod.js
import html2canvas from 'html2canvas'
import JsPDF from 'jspdf'
const generateResume = (el, name) => {
  html2canvas(el).then(canvas => {
    let contentWidth = canvas.width
    let contentHeight = canvas.height
    //一页pdf显示html页面生成的canvas高度;
    let pageHeight = (contentWidth / 592.28) * 841.89
    //未生成pdf的html页面高度
    let leftHeight = contentHeight
    //页面偏移
    let position = 0
    //a4纸的尺寸[595.28,841.89]，html页面生成的canvas在pdf中图片的宽高
    let imgWidth = 595.28
    let imgHeight = (592.28 / contentWidth) * contentHeight
    let pageData = canvas.toDataURL('image/jpeg', 1.0)
    let pdf = new JsPDF('', 'pt', 'a4')
    //有两个高度需要区分，一个是html页面的实际高度，和生成pdf的页面高度(841.89)
    //当内容未超过pdf一页显示的范围，无需分页
    if (leftHeight < pageHeight) {
      pdf.addImage(pageData, 'JPEG', 0, 0, imgWidth, imgHeight)
    } else {
      while (leftHeight > 0) {
        //arg3-->距离左边距;arg4-->距离上边距;arg5-->宽度;arg6-->高度
        pdf.addImage(pageData, 'JPEG', 0, position, imgWidth, imgHeight)
        leftHeight -= pageHeight
        position -= 841.89
        //避免添加空白页
        if (leftHeight > 0) {
          //添加新页
          pdf.addPage()
        }
      }
    }
    pdf.save(`${name}.pdf`)
  })
}
export default generateResume
 
开始使用：
 
<template>
  <div class="priview_resume_container">
    <div style="font-size: 30px" @click="getResume">点这里下载</div>
  </div>
</template>

<script>
  export default {
    name: 'priviewResume',
    methods: {
      getResume() {
        generateResume(
        document.getElementsByClassName('priview_resume_container')[0],
        '测试'
        )
      }
    },
    components: {}
  }
</script>
 
这里用class类名包裹的所有html样式都会按照vue展现的样式被canvas绘出来并以pdf文件输出

 
 
Vue下载本地pdf文件
 

html:
 
<button @click="downloadPDf">downloadPDf</button>
 
 
js:
 

 

   

    

   
   

    

      downloadPDf() {
    
   

   

    

   
   

    

             axios.post(
     'http://localhost:8080/static/test.pdf', {
    
   

   

    

   
   

    
          
     responseType: 
     'blob', 
     //重要
    
   

   

    

   
   

    

             }).then(
     response => {
    
   

   

    

   
   

    
          
     const url = 
     window.URL.createObjectURL(
     new Blob([response.data]));
    
   

   

    

   
   

    
          
     const link = 
     document.createElement(
     'a');
    
   

   

    

   
   

    
          
     let fname = 
     'report.pdf';
    
   

   

    

   
   

    

               link.href = url;
    
   

   

    

   
   

    

               link.setAttribute(
     'download', fname);
    
   

   

    

   
   

    
          
     document.body.appendChild(link);
    
   

   

    

   
   

    

               link.click();
    
   

   

    

   
   

    

             })
    
   

   

    

   
   

    

           }
    
   

   

    

   
   

    

         }
    
   
 
 
记住本地文件一定要放在static文件夹下面。

vue项目，axios去请求接口
 
request文件中代码：
 
import request from "封装好的axios请求文件"

//下载用户手册PDF时请求的接口
export const getGuide = (param) => {
    return request({
      url:"请求url",
      method:"get",
      params:param,
      //一定要加responseType
      responseType: "blob"
    })
  }
 
页面中点击下载按钮时，去请求文件流，然后执行下载操作
 代码如下：
 
downloadGuide(){
        getGuide().then(res => {
          let blob = new Blob([res], {type: 'application/pdf'});
          let downloadElement = document.createElement("a");
          let href = window.URL.createObjectURL(blob); //创建下载的链接
          downloadElement.href = href;
          downloadElement.download = `用户手册-${this.name}`    //下载后的文件名，根据需求定义
          document.body.appendChild(downloadElement);
          downloadElement.click(); //点击下载
          document.body.removeChild(downloadElement); //下载完成移除元素
          window.URL.revokeObjectURL(href); //释放掉blob对象
        })
    }