C# 上传文件

后台

public ActionResult Uploadfile()
        {
            const string savePath = "/UploadFile/File/";
            const string saveUrl = "/UploadFile/File/";
            const string fileTypes = ".xls,.xlsx";
            const int maxSize = 110000000;
            var hash = new Hashtable();
            var file = Request.Files.Get(0);
            var type = Request["type"];//type=1 文件名不重置
            if (file == null)
            {
                hash = new Hashtable();
                hash["error"] = 1;
                hash["message"] = "请选择文件";
                return Json(hash, "text/html;charset=UTF-8");
            }
            var dirPath = Server.MapPath(savePath);
            if (!Directory.Exists(dirPath))
            {
                Directory.CreateDirectory(dirPath);
            }
            var fileName = file.FileName;
            var extension = Path.GetExtension(fileName);
            if (extension != null)
            {
                var fileExt = extension.ToLower();
                var fileTypeList = ArrayList.Adapter(fileTypes.Split(','));

                if (!fileTypeList.Contains(fileExt))
                {
                    hash = new Hashtable();
                    hash["error"] = 1;
                    hash["message"] = "上传文件格式有误";
                    return Json(hash, "text/html;charset=UTF-8");
                }
                if (file.InputStream == null || file.InputStream.Length > maxSize)
                {
                    hash = new Hashtable();
                    hash["error"] = 1;
                    hash["message"] = "上传文件大小超过限制";
                    return Json(hash, "text/html;charset=UTF-8");
                }
                var newFileName = type == "1" ? fileName : DateTime.Now.ToString("yyyyMMddHHmmss_ffff", DateTimeFormatInfo.InvariantInfo) + fileExt;
                var filePath = dirPath + newFileName;
                file.SaveAs(filePath);
                var fileUrl = saveUrl + newFileName;
                hash = new Hashtable();
                hash["error"] = 0;
                hash["url"] = fileUrl;
            }
            return Json(hash, "text/html;charset=UTF-8");
        }

前台 layui

//上传excel
    upload.render({
        elem: '#UploadFile'
        , url: '/Home/UploadFile?path=beforeExamInfo&sign=2'
        , accept: 'file' //普通文件
        , exts: 'xls|xlsx' //只允许上传Excel文件
        , choose: function (obj) {
            layer.msg('数据上传中...', {
                icon: 16,
                shade: 0.01,
                time: 0
            })
        }
        , done: function (res) {
            layer.close(layer.msg());
            if (res.error != 0) {
                layer.alert("上传失败:<br/>" + res.message, { icon: 5 });
            }
            else {
                layer.msg("上传成功", { icon: 6, time: 1000 });
                active["reload"].call();
            }
        }
    });