<form data-ajax-success="AfterUpload" enctype="multipart/form-data" id="frm">
        <input type="file" name="fileBase" value="http://www.mamicode.com/" id="imgUpload" class="jiangli_1_w" />
        <input type="submit" id="btnSub" value="http://www.mamicode.com/上传图片" /> <span class="flat_loe">上传图片宽度最大尺寸720px，高度无限制</span>
 </form>

 //上传图片
           $("#btnSub").click(function () {
                $("#frm").ajaxSubmit({
                    url: "/Slide/UploadImage",
                    type: "Post",
                    success: AfterUpload
                });
                return false;
            });

 　　　　function AfterUpload(msg) {
            if (msg != "0") {
                $("#imgPath").removeAttr("src").attr("src", msg);
            } else {
                swal({
                    title: "温馨提示",
                    text: "图片格式有误"
                });
                $("#imgPath").val("");
                return false;
            }
        }

      /// <summary>
        /// 上传图片
        /// </summary>
        /// <param name="fileBase"></param>
        /// <returns></returns>
        [HttpPost]
        public ActionResult UploadImage(HttpPostedFileBase fileBase)
        {
            string imgurl = string.Empty;
            string imgPath = System.IO.Path.GetFileName(fileBase.FileName);
            int index = imgPath.LastIndexOf(‘.‘);
            string suffix = imgPath.Substring(index).ToLower();
            if (suffix == ".jpg" || suffix == ".jpeg" || suffix == ".png" || suffix == ".gif" || suffix == ".bmp")
            {
                string pictureName = DateTime.Now.Ticks.ToString() + suffix; //图片名称
                string savePath = Server.MapPath("/Files/Images/SlideConfig/");//幻灯片文件夹
                if (!Directory.Exists(savePath))
                {
                    Directory.CreateDirectory(savePath);
                }
                imgurl = "http://" + Request.Url.Authority + "//Files/Images/SlideConfig/" + pictureName;
                fileBase.SaveAs(savePath + pictureName);
            }
            else
            {
                imgurl = "0";
            }
            return Content(imgurl);
        }