码迷,mamicode.com
首页 > 其他好文 > 详细

批量下载文件示例

时间:2020-09-11 16:18:03      阅读:56      评论:0      收藏:0      [点我收藏+]

标签:on()   ack   dir   ace   emif   批量   sig   The   base   

一、此方法火狐有些版本是不支持的

 

window.location.href = ‘https://*****.oss-cn-**.aliyuncs.com/*********‘;

二、为了解决火狐有些版本不支持,可以改成这种方式

 

window.location=‘https://*****.oss-cn-**.aliyuncs.com/*********‘;

三、该方法IE和火狐都可以,url表示要下载的文件路径:

 

function(url){

    try {

          var elemIF = document.createElement("iframe");

          elemIF.src = url;

          elemIF.style.display = "none";

          document.body.appendChild(elemIF);

        } catch (e) {

          alert("下载异常!");

        }

}

四、form表单的形式

 

 

 

 

downloadFile(url){

      var form=$("<form>");

      form.attr("style","display:none");

      form.attr("target","");

      form.attr("method","get");

     form.attr("action",url);

      $("body").append(form);

      form.submit();//表单提交}

}

五、a标签的方式

 

function(url,name){

    var a = document.createElement("a");

     a.download = name + ".xls";

     a.href = url;

     $("body").append(a); // 修复firefox中无法触发click

     a.click();

     $(a).remove();

}

六、假如后台给的文件流

 

 

 

 

function (formData, url, name) {

  return new Promise((resolve, reject) => {

    var xhr = new XMLHttpRequest();

    xhr.open("POST", url, true); // 也可以使用POST方式,根据接口

    xhr.responseType = "blob"; // 返回类型blob

    // 定义请求完成的处理函数,请求前也可以增加加载框/禁用下载按钮逻辑

    xhr.onload = function () {

      // 请求完成

      if (this.status === 200) {

        // 返回200

        var blob = this.response;

        var reader = new FileReader();

        reader.readAsDataURL(blob); // 转换为base64,可以直接放入a表情href

        reader.onload = function (e) {

          // 转换完成,创建一个a标签用于下载

          var a = document.createElement("a");

          a.download = name + ".xls";

          a.href = e.target.result;

          $("body").append(a); // 修复firefox中无法触发click

          a.click();

          resolve(200)

          $(a).remove();

        };

      }

    };

    // 发送ajax请求

    xhr.send(formData);

  })

};

七、download.js

我粘贴一下download的源码

 

//download.js v4.2, by dandavis; 2008-2016. [CCBY2] see http://danml.com/download.html for tests/usage

// v1 landed a FF+Chrome compat 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

 

(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 () {

 

    return function download(data, strFileName, strMimeType) {

 

        var self = window, // this script is only for browsers anyway...

            defaultMime = "application/octet-stream", // this default mime also triggers iframe downloads

            mimeType = strMimeType || defaultMime,

            payload = data,

            url = !strFileName && !strMimeType && payload,

            anchor = document.createElement("a"),

            toString = function(a){return String(a);},

            myBlob = (self.Blob || self.MozBlob || self.WebKitBlob || toString),

            fileName = strFileName || "download",

            blob,

            reader;

            myBlob= myBlob.call ? myBlob.bind(self) : Blob ;

     

        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(url && url.length< 2048){ // if no filename and no mime, assume a url was passed as the only argument

            fileName = url.split("/").pop().split("?")[0];

            anchor.href = url; // assign href prop to temp anchor

              if(anchor.href.indexOf(url) !== -1){ // 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.οnlοad= function(e){

                  download(e.target.response, fileName, defaultMime);

                };

                setTimeout(function(){ ajax.send();}, 0); // allows setting custom ajax headers using the return:

                return ajax;

            } // end if valid url?

        } // end if url?

 

 

        //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

            }

            

        }//end if dataURL passed?

 

        blob = payload instanceof myBlob ?

            payload :

            new myBlob([payload], {type: mimeType}) ;

 

 

        function dataUrlToBlob(strUrl) {

            var parts= strUrl.split(/[:;,]/),

            type= parts[1],

            decoder= parts[2] == "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){

 

            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";

                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)) {

                url=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){ // 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.οnlοad=function(e){

                saver(this.result);

            };

            reader.readAsDataURL(blob);

        }

        return true;

    }; /* end download() */

}));

用法:

 

download(fileUrl,name,"video/mp4");

 

具体更多的用法请参考官网,

 

注意 download.js第一个参数 是数据流,不是像oss那样的文件地址

 

详细的配置信息可以参考我写的这篇文章:http://blog.ncmem.com/wordpress/2019/08/28/java%e6%89%b9%e9%87%8f%e4%b8%8b%e8%bd%bd/ 

 

批量下载文件示例

标签:on()   ack   dir   ace   emif   批量   sig   The   base   

原文地址:https://www.cnblogs.com/songsu/p/13588673.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!