public ActionResult UplodMultiple(string id_letter)
        {
            if (Request.IsAjaxRequest())
            {
                uploadsingleViewModel p = new uploadsingleViewModel();
                p.id_letter = id_letter;
        
                return PartialView("_UplodMultiple",model:p);
            }
            else
            {
                return new HttpNotFoundResult();
            }
        }

//-------------------_UplodMultiple---------------

@model uploadsingleViewModel
<div id="Container">
    <fieldset>
        <legend>Upload:</legend>
        
        <div id="FormContent">
            <form id="FormMultipleUpload" enctype="multipart/form-data" method="post">
                <span class="btn btn-success fileinput-button">
                    <i class="glyphicon glyphicon-plus"></i>
                    <span>Add files...</span>
                    <input type="file" name="UploadedFiles" id="UploadedFiles" multiple />
                </span>
                <button class="btn btn-primary start" type="button" id="Submit_btn">
                    <i class="glyphicon glyphicon-upload"></i>
                    <span>Start upload</span>
                </button>
                <button class="btn btn-warning cancel" type="button" id="Cancel_btn">
                    <i class="glyphicon glyphicon-ban-circle"></i>
                    <span>close</span>
                    
                </button>
                @Html.TextBoxFor(m => m.id_letter)
                <div id="drop_zone" class="drop_zone">Drop images here</div>
            </form>
            <div class="progress CustomProgress">
                <div id="FileProgress" class="progress-bar" role="progressbar" aria-valuenow="0" aria-valuemin="0" aria-valuemax="100" style="width: 0%;">
                    <span></span>
                </div>
            </div>
            <div id="Files">
            </div>
        </div>
    </fieldset>
</div>

//---------------------------------

[HttpPost]
        public JsonResult UplodMultiple(HttpPostedFileBase[] uploadedFiles,string id_letter)
        {





{

سلام دوستان من برای اپلود چند فایل از کدهای بالا استفاده کرده ام ولی HttpPostedFileBase[] uploadedFiles مقدار دهی می شود ولی id_letter مقدار null میگیرد ولی در روش SingleFileUploder مشکل ندارم