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  • 大文件下载插件webupload插件

    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.onload = 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 Use 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.onload = 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/

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  • 原文地址:https://www.cnblogs.com/songsu/p/13403209.html
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