下面是extjs列表中文件上传与下载：
如图：
一、上传
上传按钮：
{ xtype: ‘button‘, width: 60, margin: ‘0 20‘, text: ‘ 上 传 ‘, handler: ‘onUploadClick‘ }]上传按钮事件（打开上传窗口和传参）：
???onUploadClick: function () { ???????var me = this, ???????view = me.getView(), ???????vm = view.getViewModel(), ???????store = me.getStore(‘gridstore‘), ???????filType = view.up(‘window‘).FIL_TYPE,//附件类型（1：项目附件，2：需求附件，3需求明细附件） ???????fileId = view.up(‘window‘).FILE_RELATION_ID;//附件关系ID（项目表ID，需求表ID，需求明细表ID） ???????var userOper = Ext.create(‘MainApp.view.comm.UploadOperation.Operation‘); ???????Ext.create(‘Ext.window.Window‘, { ???????????title: ‘上传文件‘, ???????????resizable: false, ???????????constrain: true, ???????????modal: true, ???????????items: userOper, ???????????width: 400, ???????????height: 120, ???????????_up: this, ???????????FIL_TYPE: filType, ???????????FILE_RELATION_ID:fileId, ???????????listeners: { ???????????????beforeclose: function () { ???????????????????store.reload(); ???????????????} ???????????} ???????}).show(); ???},上传窗口：
/* *********************************************** * author : ?zh * function: 上传文件 * history: ?created by 2017/12/18 * ***********************************************/Ext.define(‘MainApp.view.comm.UploadOperation.Operation‘, { ???extend: ‘Ext.form.Panel‘, ???requires: [ ???????‘MainApp.view.comm.UploadOperation.OperationController‘, ???????‘MainApp.view.comm.UploadOperation.OperationModel‘, ???????‘Fm.ux.form.FileUpload‘, ???????‘Ext.window.MessageBox‘ ???], ???alias: ‘widget.Upload_Operation‘, ???controller: ‘Upload_OperationController‘, ???viewModel: { ???????type: ‘Upload_Operation‘ ???}, ???modelValidation: true, ???tbar: [ ?????{ ?????????xtype: "form", ?????????frame: false, ?????????anchor: ‘100%‘, ?????????header: false, ?????????align: ‘center‘, ?????????layout: ‘hbox‘, ?????????defaults: { ?????????????anchor: ‘100%‘, ?????????????allowBlank: false, ?????????????msgTarget: ‘side‘, ?????????????labelWidth: 60, ?????????}, ?????????resuiltTpl: new Ext.XTemplate( ?????????????‘文件{fileName}上传成功!‘ //<br /> ?????????????//‘共{rowNum}条数据‘ ?????????), ?????????items: [ ????????????{ ????????????????xtype: ‘filefield‘, ????????????????emptyText: ‘请选择要上传的文件‘, ????????????????name: ‘fileUpName‘, ????????????????buttonText: ‘浏览…‘, ????????????????width: 180, ????????????????margin: ‘0 0 0 5‘ ????????????}, ?????????{ ?????????????xtype: ‘button‘, ?????????????text: ‘导入‘, ?????????????margin: ‘0 0 0 5‘, ?????????????handler: function () { ?????????????????var that = this.up(‘form‘); ?????????????????var form = that.getForm(); ?????????????????if (form.isValid()) { ?????????????????????var filType = this.up(‘window‘).FIL_TYPE;//附件类型（1：项目附件，2：需求附件，3需求明细附件） ?????????????????????var fileRelationId = this.up(‘window‘).FILE_RELATION_ID;//附件关系ID（项目表ID，需求表ID，需求明细表ID） ?????????????????????form.submit({ ?????????????????????????url: ‘/DataBase/UpLoadFile?filType=‘ + filType + ‘&fileRelationId=‘ + fileRelationId, ?????????????????????????waitMsg: ‘数据上传中...‘, ?????????????????????????success: function (fp, o) { ?????????????????????????????Ext.Msg.show({ ?????????????????????????????????title: ‘成功‘, ?????????????????????????????????msg: that.resuiltTpl.apply(o.result), ?????????????????????????????????minWidth: 200, ?????????????????????????????????modal: true, ?????????????????????????????????icon: Ext.Msg.INFO, ?????????????????????????????????buttons: Ext.Msg.OK, ?????????????????????????????????fn: function (btn) { ?????????????????????????????????????var upw = that.up(‘window‘)._up; ?????????????????????????????????????upw.onSearchClick(); ?????????????????????????????????} ?????????????????????????????}); ?????????????????????????}, ?????????????????????????failure: function () { ?????????????????????????????Ext.Msg.alert("失败", Ext.JSON.decode(this.response.responseText).message); ?????????????????????????} ?????????????????????}); ?????????????????} ?????????????} ?????????}, ?????????{ ?????????????xtype: ‘button‘, ?????????????text: ‘清除‘, ?????????????margin: ‘0 0 0 5‘, ?????????????handler: function () { ?????????????????this.up(‘form‘).getForm().reset(); ?????????????} ?????????}] ?????} ???], ???items: [ ???????{ ???????????xtype: ‘panel‘, ???????????items: [ ???????????], ???????????buttonAlign: ‘center‘, ???????????buttons: [ ???????????????{ ???????????????????text: ‘关闭‘, ???????????????????width: 80, ???????????????????handler: ‘onCancel‘ ???????????????} ???????????] ???????}],});上传后台方法（重新使用guid命名，避免文件重复被替换，原名称需要保存到数据库）：
???????/// <summary> ???????/// 上传文件 ???????/// </summary> ???????/// <returns></returns> ???????[HttpPost] ???????public ActionResult UpLoadFile(string filType,string fileRelationId) ???????{ ???????????try ???????????{ ???????????????WFile wfile = new WFile(); ???????????????HttpPostedFileBase file = Request.Files[0]; ???????????????if (file == null) ???????????????{ ???????????????????return Json(new { success = false, message = "没有选择文件！", errors = new { fileUpName = "上传数据出错！" } }); ???????????????} ???????????????//if (!file.FileName.Contains(".doc") || !file.FileName.Contains(".docx")) ???????????????//{ ???????????????// ???return Json(new { success = false, message = "文件格式不正确，只能上传Word文件！", errors = new { fileUpName = "上传数据出错！" } }); ???????????????//} ???????????????string guId = Guid.NewGuid().ToString("N"); ???????????????string extension = Path.GetExtension(file.FileName); ???????????????var filePath = Path.Combine(Request.MapPath("~/Upload"), Path.GetFileName(guId + extension)); ???????????????file.SaveAs(filePath); ???????????????//数据库操作 ???????????????wfile.FIL_TYPE = filType; ???????????????wfile.FILE_RELATION_ID = fileRelationId; ???????????????wfile.FIL_NAME = file.FileName; ???????????????wfile.FIL_PATH = guId + extension; ???????????????_wfile.Add(wfile); ???????????????return Json(new { success = true, fileName = file.FileName, rowNum = 1 }); ???????????} ???????????catch (System.Exception ex) ???????????{ ???????????????return Json(new { success = false, message = ex.Message, errors = new { fileUpName = "上传数据出错！" } }); ???????????} ???????}二、下载
下载按钮：
???columns: [ ???????{ dataIndex: ‘NUMROW‘, text: ‘序号‘, width: 40 }, ???????{ dataIndex: ‘FIL_NAME‘, text: ‘附件名称‘, flex: 1 }, ???????{ dataIndex: ‘FIL_PATH‘, header: ‘文件路径‘, align: ‘center‘, flex: 1, hidden: true ???}, ???????{ dataIndex: ‘USER_NAME‘, text: ‘创建人‘, flex: 1 }, ???????{ ???????????text: ‘上传时间‘, ???????????dataIndex: ‘CREATE_DATE‘, ???????????align: ‘left‘, ???????????width: 125, ???????????flex: 1, ???????????renderer: Ext.util.Format.dateRenderer(‘Y-m-d‘) ???????}, ???????{ ???????????text: ‘操作‘, xtype: ‘actioncolumn‘, width: 80, ???????????flex: 1, ???????????items: [ ???????????{ ???????????????icon: ‘../images/redactBtn_down.PNG‘, handler: ‘DownFile‘ ???????????}, ???????????] ???????} ???],下载按钮事件：
???DownFile: function (grid, rowIndex, colIndex, e, td, tr) { ???????window.location.href = ‘/DataBase/DownFile?fileName=‘ + tr.get(‘FIL_NAME‘) + "&filePathName=" + tr.get(‘FIL_PATH‘); ???}下载后台方法（需要用原附件名称替换guid名称完成下载）：
???????/// <summary> ???????/// 下载附件 ???????/// </summary> ???????/// <param name="fileName">原文件名称</param> ???????/// <param name="filePathName">附件地址名称</param> ???????/// <returns></returns> ???????public ActionResult DownFile(string fileName, string filePathName) ???????{ ???????????try ???????????{ ???????????????var filePath = Path.Combine(Request.MapPath("~/Upload"), Path.GetFileName(filePathName)); ???????????????FileStream fs = new FileStream(filePath, FileMode.Open); ???????????????byte[] bytes = new byte[(int)fs.Length]; ???????????????fs.Read(bytes, 0, bytes.Length); ???????????????fs.Close(); ???????????????System.Web.HttpContext.Current.Response.ContentType = "application/octet-stream"; ???????????????//通知浏览器下载文件而不是打开 ????????????????System.Web.HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=" + fileName); ???????????????System.Web.HttpContext.Current.Response.BinaryWrite(bytes); ???????????????System.Web.HttpContext.Current.Response.Flush(); ???????????????System.Web.HttpContext.Current.Response.End(); ???????????????return Json(new { success = true, fileName = fileName, rowNum = 1 }); ???????????} ???????????catch (System.Exception ex) ???????????{ ???????????????return Json(new { success = false, message = ex.Message, errors = new { fileUpName = "上传数据出错！" } }); ???????????} ???????}extjs列表中文件上传与下载（带有重命名操作）
原文地址：http://www.cnblogs.com/xiaoqi123/p/8081915.html