asp.net使用H5新特性实现异步上传的示例_实用技巧_

 function formDataUpload() { //这里可以一次性选中多个文件 var fileUpload = document.getElementById("FileToUpload").files; if (fileUpload.length == 0) { alert("请选中文件再上传"); return; } //html5新特性 var formdata = new FormData(); //添加上传数据 for (var i = 0; i < fileUpload.length;i++){ formdata.append('files', fileUpload[i]); } //使用javascript的原生ajax var xmlHttp = new XMLHttpRequest(); xmlHttp.open("post", 'Handler.ashx?method=formDataUpload'); xmlHttp.onreadystatechange = function () { if (xmlHttp.readyState == 4 && xmlHttp.status == 200) { alert("上传成功"); } } xmlHttp.send(formdata); } 

<%@ WebHandler Language="C#" Class="Handler" %> using System; using System.Web; public class Handler : IHttpHandler { public void ProcessRequest (HttpContext context) { formDataUpload(context); } public static void formDataUpload(HttpContext context) { //获取到客户端提交的文件 HttpFileCollection files = context.Request.Files; string msg = string.Empty; string error = string.Empty; int fileM = 0; if (files.Count > 0) { for (int i = 0; i < files.Count; i++) { ; String path = @"D:\"+files[i].FileName; files[i].SaveAs(path); fileM += files[i].ContentLength; } msg = "上传成功，文件总大小:" + fileM; string res = "{error :'" + error + "',msg:'" + msg + "'}"; context.Response.Write(res); context.Response.End(); } } public bool IsReusable { get { return false; } } }