uploadify上传带参数及接收参数的方法

function uploadify() {
        $("#uploadify").uploadify({
            method:'post',
            uploader: '/Manage/Order/SubmitUploadify',
            swf: '/Content/scripts/plugins/uploadify/uploadify.swf',
            buttonText: "上传文件",
            height: 30,
            width: 110,
            fileTypeExts: '*.jpg;*.doc;*.docx;*.pdf;*.png',
            fileSizeLimit: '10MB',
            multi: false,
            formData: "ContractCode":"20170222","UserId":"20125"
            },
            onUploadStart: function (file) {
                some code...
            },
            onUploadSuccess: function (file, data, response) {
                var obj = jQuery.parseJSON(data); 
                if (obj.State) {
                    $("#ContractFile").val(obj.FilePath);
                }
            },
            onUploadError: function (file) {
                $("#" + file.id).prepend('<span class="error" title="失败"><i class="fa fa-exclamation-circle"></i></span>');
            }
        });
        $("#uploadify-button").prepend('<i style="opacity: 0.6;" class="fa fa-cloud-upload"></i>&nbsp;');
    }

[HttpPost]
public ActionResult SubmitUploadify(HttpPostedFileBase fileData,string contractCode,string userId)
{
   string formatFilePath = string.Format("~/Uploads/ContractFile/{0}", contractCode);
   ResultUpload rst = UploadHelper.Uploadify(fileData, formatFilePath);
   return Content(rst.ToJson());
}