1、前端

     
     
           
       上 传  
     

$("#btn").click(function () {        var files = document.getElementById("upfile").files;        if (files.length == 0) {            alert("请选择文件");            return;        }        var formdata=new FormData();        formdata.append("file", files[0]);        $.ajax({            url: "/home/upload",            type: "post",            data: formdata,            contentType: false,            processData: false,            success: function (data) {                if (data == "ok") {                    alert("成功");                } else {                    alert("失败");                }            }        });    });

2、后端

[HttpPost]        public ActionResult upload(HttpPostedFileBase file)        {            try            {                var filename = Path.GetFileName(file.FileName);                var path = Path.Combine(Server.MapPath("/"), filename);                file.SaveAs(path);                return Content("ok");            }            catch (Exception ex)            {                return Content(ex.Message);            }        }