先给大家展示下效果图：

///作者：柯锦///完成时间：2016.08.16///多文件异步上传带进度条(function ($) {function bytesToSize(bytes) {if (bytes === 0) return '0 B';var k = 1024, // or 1000sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'],i = Math.floor(Math.log(bytes) / Math.log(k));return (bytes / Math.pow(k, i)).toPrecision(3) + ' ' + sizes[i];}function changeCursor(obj) {obj.style.cursor = 'pointer'}function deleteSelfAndFile(obj) {var that = $(obj);var parentLi = that.parent("li");that.remove();parentLi.remove();}function CreateXMLHttpRequest(target) {var xhr = new XMLHttpRequest();//var ops = $.data(target, "KJajaxUpload").Options;//var v, h, evs = { loadstart: 0, loadend: 0, progress: 0, load: 0, error: 0, abort: 0 };//for (v in evs) {// if (h = ops['on' + v]) {// xhr.upload.addEventListener(v, h, false);// }//}return xhr;}function InitFileDiv(target, options) {var _that = $(target);var width = _that.width();var hasUploadedDiv = $("<div class='KJajaxUpload_HasUploaded'/>");hasUploadedDiv.css({width: "100%"});_that.append(hasUploadedDiv);// 上var divClear = $("<div style='clear:both;'></div>");var divUploadBody = $("<div class='KJajaxUpload_Body'/>");var divLeft = $("<div class='KJajaxUpload_Left'/>");var divRight = $("<div class='KJajaxUpload_Right'/>");var uploadButton = $("<input type='button' class='KJajaxUpload_Button' value='Select File' />");if (options.Text) {uploadButton.val(options.Text);}uploadButton.click(function () {SelectFiles(target);})uploadButton.css({width: 80})if (options.Available) {uploadButton.prop("disabled", false);} else {uploadButton.prop("disabled", true);}divUploadBody.css({"overflow": "hidden"})divLeft.css({float: "left",width: "100%"})divRight.css({float: "left","margin-left": " -20px"})_that.append(divClear);divLeft.append(uploadButton);// 左 buttondivLeft.append("<font style='font-size:12px;color:red;margin-left:2px;'>可多选</font>")divUploadBody.append(divLeft);// 左divUploadBody.append(divRight);// 右 文件列表_that.append(divUploadBody);return _that;}/// 创建蒙版function CreateMark(target) {var mark;var width = $(document.body).width() / 2 - 200;mark = $("<div>");mark.css({width: "100%",height: "100%",position: "fixed",left: 0,top: 0,opacity: 0.5,"z-index": 8,"background-color": "#EFEFF2","display": "none"});var contentText = $("<div class='KJajaxUpload_upload_wrapper'>");contentText.html("文件上传中，请稍后...");contentText.css({"text-align": "center",width: "400px","padding-bottom": "50px","z-index": 9,position: "fixed",left: width + "px","top": "50%","background-color": "white","display": "none"})contentText.appendTo($("body"));mark.appendTo($("body"));return mark;}///创建进度条function CreateUploadBar(target) {var contentText = $(".KJajaxUpload_upload_wrapper");var fileDiv = $(target);// $.data(target, "KJajaxUpload").FileDiv;var FileList = fileDiv.find(".fileuploadlist.newfilelist");$.each(FileList, function (i) {var fileName = $(this).attr("filename");var divid = $(this).attr("id");var proressDiv = $("<div id='KJajaxUpload_progress_" + i + "' />");var fileNameLable = $("<span >" + fileName + "</span>");var barDiv = $("<div id='KJajaxUpload_bar_" + divid + "' name='KJajaxUpload_bar_" + fileName + "'/>");barDiv.css({width: "350px","margin-left": "20px",height: "22px",border: "1px solid black ","line-height": "22px"})var barText1 = $("<div class='KJajaxUpload_progresstext'/>");barText1.css({"text-align": "center","position": "absolute",width: "350px"});barText1.html("0%");var barText2 = $("<div class='KJajaxUpload_progresstext'/>");barText2.css({"text-align": "center",width: "350px","background-color": "#ffe48d"});barText2.html("0%");var barValue = $("<div class='KJajaxUpload_progressvalue'>");barValue.css({position: "relative",overflow: "hidden",width: "0px"})barValue.append(barText2);barDiv.append(barText1);barDiv.append(barValue);proressDiv.append(fileNameLable);contentText.append(proressDiv);contentText.append(barDiv);});}function ChangeProcess(filename, evt) {var loaded = evt.loaded; //已经上传大小情况 var tot = evt.total; //附件总大小 var per = Math.floor(100 * loaded / tot); //已经上传的百分比 var that = $("[name='KJajaxUpload_bar_" + filename + "']");that.find('div.KJajaxUpload_progressvalue').css("width", per + "%");that.find('div.KJajaxUpload_progresstext').html(per + "%");}///选择文件function SelectFiles(target) {var options = $.data(target, "KJajaxUpload").Options;var deleteButtonUrl = options.deleteButtonUrl;var ele = $("<input type='file'/>");ele.prop("multiple", options.multiple !== false);ele.hide();ele.change(function (e) {var exist = false;var files = e.target.files;var filenames = GetalreadyExistFileNames(target);for (var item in files) {var file = files[item];if ($.inArray(file.name, filenames) > -1) {exist = true;break;}}if (!exist) {var ul = $("<ul style='margin:0px;'/>");for (var i = 0, n = files.length; i < n; i++) {var deletebutton = $("<img src='" + deleteButtonUrl + "' onmouseover='changeCursor(this)' class='deleteBtn' />");deletebutton.click(function () {deleteSelfAndFile(this);})var guid = new GUID().New();var li = $('<li class="fileuploadlist newfilelist" id="' + guid + '" filename="' + files[i].name + '" >' + files[i].name + ' (' + bytesToSize(files[i].size) + ' )</li>');li.append(deletebutton);ul.append(li);}$(target).find(".KJajaxUpload_Right").append(ul);options.onChange.call(this, e);} else {alert("文件名重复");ele.remove();return}});$(target).append(ele);ele.click();}/// 获取已经存在的文件名列表function GetalreadyExistFileNames(target) {var that = $(target);var fileExists = that.find(".fileuploadlist");var fileNames = [];/// 还存在的文件列表fileExists.each(function () {var filename = $(this).attr("filename");if ($.inArray(filename, fileNames) == -1) {fileNames.push(filename);}})return fileNames;}/// 上传文件function UploadFiles(target) {var that = $(target);var fileInputs = that.find(":file");var options = $.data(target, "KJajaxUpload").Options;var deleteButtonUrl = options.deleteButtonUrl;var onUploaded = options.onUploaded;if (fileInputs.length > 0) {var total = 0;var uploaded = 0;var reponses = [];var mark = $.data(target, "KJajaxUpload").Mark;var markcontent = $(".KJajaxUpload_upload_wrapper");mark.show();markcontent.show();CreateUploadBar(target);var fileExists = that.find(".fileuploadlist");var fileNames = [];/// 还存在的文件列表fileExists.each(function () {var filename = $(this).attr("filename");if ($.inArray(filename, fileNames) == -1) {fileNames.push(filename);}})for (var i = 0; i < fileInputs.length; i++) {var fileinput = fileInputs[i];var files = fileinput.files;if (files.length > 0) {for (var j = 0, n = files.length; j < n; j++) {if ($.inArray(files[j].name, fileNames) > -1) {total++;var filename = files[j].name;var paramData = options.formData;var data = new FormData();data.append("uploadedfile[" + j + "]", files[j]);if (paramData != null) {for (var k in paramData) {data.append(k, paramData[k]);}}var xhr = CreateXMLHttpRequest(target);xhr.upload.addEventListener("progress",function (data) {return function (e) {ChangeProcess(data, e);}}(filename), false);xhr.upload.addEventListener("loadend", function () {}, false);xhr.upload.addEventListener("load", function () {uploaded++;}, false);xhr.onreadystatechange = function () {if (this.readyState == 4) {// 4 = "loaded"if (this.status == 200) {// 200 = OK reponses.push(this.responseText);if (uploaded == $.data(target, "KJajaxUpload").TotalFiles) {var HasUploaded = that.find(".KJajaxUpload_HasUploaded");var ul = $("<ul style='margin:0px;'/>");for (var t = 0; t < reponses.length; t++) {var files = JSON.parse(reponses[t]);for (var i = 0, n = files.length; i < n; i++) {var deletebutton = $("<img src='" + deleteButtonUrl + "' onmouseover='changeCursor(this)' class='deleteBtn' />");deletebutton.click(function () {deleteSelfAndFile(this);})var guid = new GUID().New();var li = $('<li class="fileuploadlist" id="' + guid + '" filename="' + files[i].Name + '" filepath="' + files[i].FilePath + '" ><a target="_blank" href="' + files[i].FileUrl + '">' + files[i].Name + '</a> </li>');li.append(deletebutton);ul.append(li);}}that.find(".KJajaxUpload_Right").empty();HasUploaded.append(ul);fileInputs.remove();Uploaded(target);var data = GetAlreadyUploadedFiles(target);onUploaded.call(null, data);}}else {alert("Problem retrieving XML data");}}};xhr.open("POST", options.url, true);xhr.send(data);}}var state = $.data(target, "KJajaxUpload");state.TotalFiles = total;$.data(this, "KJajaxUpload", state);}}} else {var data = GetAlreadyUploadedFiles(target);onUploaded.call(null, data);}return that;}/// 上传完毕function Uploaded(target) {alert("文件上传完毕");var mark = $.data(target, "KJajaxUpload").Mark;var markcontent = $(".KJajaxUpload_upload_wrapper");mark.hide();markcontent.hide();var that = $(target);var fileInputs = that.find(":file");fileInputs.remove();}///初始化已有的数据function AlreadFiles(target, options) {var that = $(target);var deleteButtonUrl = options.deleteButtonUrl;var files = options.AlreadFiles;var HasUploaded = that.find(".KJajaxUpload_HasUploaded");if (files.length > 0) {var ul = $("<ul style='margin:0px;'/>");for (var i = 0, n = files.length; i < n; i++) {var deletebutton = $("<img src='" + deleteButtonUrl + "' onmouseover='changeCursor(this)' class='deleteBtn' />");deletebutton.click(function () {deleteSelfAndFile(this);})var pos = files[i].lastIndexOf("\\");var filepos = files[i].lastIndexOf("uploadFile");var reg = /[\\\/]/g;var filePath = files[i];var fileUrl = files[i].substr(filepos).replace(reg, '/');var fileName = files[i].substr(pos + 1);fileName = fileName.substr(fileName.lastIndexOf("_S_") + 3);var guid = new GUID().New();var li = $('<li class="fileuploadlist" id="' + guid + '" filename="' + fileName + '" filepath="' + filePath + '" ><a target="_blank" href="' + fileUrl + '">' + fileName + '</a> </li>');li.append(deletebutton);ul.append(li);}HasUploaded.append(ul);}}function GetAlreadyUploadedFiles(target) {var that = $(target);var HasUploaded = that.find(".KJajaxUpload_HasUploaded li");var datas = [];HasUploaded.each(function () {var data = {};data.name = $(this).attr("filename");data.filepath = $(this).attr("filepath");data.fileurl = $(this).find("a").attr("href");datas.push(data);})return datas;}$.fn.KJajaxUpload = function (options, param) {var that = this;if (typeof options == "string") {var method = $.fn.KJajaxUpload.Methods[options];if (method) {return method(this, param);}}options = options || {};return this.each(function () {var that = this;var state = $.data(this, "KJajaxUpload");if (state) {$.extend(state.Options, options);} else {var _options = $.extend({}, $.fn.KJajaxUpload.Default, options);InitFileDiv(this, _options);AlreadFiles(this, _options);state = $.data(this, "KJajaxUpload", {Options: _options,Mark: CreateMark(this),TotalFiles: 0});}})}$.fn.KJajaxUpload.Default = {url: '/Ashx/UploadFilesHandler.ashx?r=' + Math.random(),formData: {},//要传递的参数Text: "选择文件",ContinueAddText: "继续添加",multiple: true,AlreadFiles: [],// 初始化已经存在的文件Available: true,// 可用的deleteButtonUrl: '/Style/images/delete.jpg',onInit: function () { },onChange: function () { },onUploaded: function () { }// 文件上传完毕后的回调函数};$.fn.KJajaxUpload.Methods = {options: function (jq) {return $.data(jq[0], "KJajaxUpload").Options;},upload: function (jq) {return UploadFiles(jq[0]);}};})(jQuery)

后端代码

/// <summary>/// UploadFilesHandler 的摘要说明/// </summary>public class UploadFilesHandler : IHttpHandler{public void ProcessRequest(HttpContext context){List<FileReponse> list = new List<FileReponse>();string filePath = System.AppDomain.CurrentDomain.BaseDirectory.ToString() + @"uploadFile\" + DateTime.Now.Year.ToString() + @"\" + DateTime.Now.Month.ToString() + @"\" + DateTime.Now.Day.ToString() + @"\" + System.Web.HttpUtility.UrlDecode(context.Request.Params["userName"].ToString()) + @"\";if (context.Request.Files.Count > 0){if (!Directory.Exists(filePath)){Directory.CreateDirectory(filePath);}try{foreach (string files in context.Request.Files){HttpPostedFile upfile = context.Request.Files[files];int bufferSize = 1024 * 50;//50Kstring _guid = Guid.NewGuid().ToString().Replace("-", "");byte[] buffer = new byte[bufferSize];int currentCounts = 0;//long totalLength = upfile.ContentLength;string name = upfile.FileName.Substring(upfile.FileName.LastIndexOf("\\") + 1);string fileName = filePath + _guid + "_S_" + name;using (FileStream fs = new FileStream(fileName, FileMode.Create)){while (currentCounts < totalLength){int bytes = upfile.InputStream.Read(buffer, 0, bufferSize);fs.Write(buffer, 0, bytes);//Thread.Sleep(1);//0.001scurrentCounts += bytes;}}FileReponse item = new FileReponse();item.Name = name;item.FilePath = fileName;int filepos = item.FilePath.LastIndexOf("uploadFile");item.FileUrl = item.FilePath.Substring(filepos);list.Add(item);}}catch (Exception ex){}}string reponse = JsonConvert.SerializeObject(list);context.Response.Write(reponse);//context.Response.ContentType = "text/plain";//context.Response.Write("Hello World");}public bool IsReusable{get{return false;}}}internal class FileReponse{public string Name { get; set; }public string FilePath { get; set; }public string FileUrl { get; set; }}

使用：

var config = {};config.formData = formData;if (!HasTheRight("HDComplaintsArea")) {config.Available = false;}if (record.Attachments) {config.AlreadFiles = record.Attachments;}config.onUploaded = function (data) {save(data);}$("#filediv").KJajaxUpload(config);$("#btnSave").click(function () {$("#filediv").KJajaxUpload("upload");})function save(data) {fields.Attachments = [];for (var i = 0; i < data.length; i++) {fields.Attachments.push(data[i].filepath);} fields.Attachments = JSON.stringify(fields.Attachments);}

以上所述是小编给大家介绍的jQuery多文件异步上传带进度条实例代码，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对网站的支持！