.net core mvc controls are combined uploadify image upload

Back-end code:

/// <summary>
        /// 图片上传，上传路径： "/Uploads/Images/" + folder + "/" + saveName
        /// </summary>
        /// <param name="fileData"></param>
        /// <returns></returns>
        [HttpPost]
        public JsonResult UploadImage([FromServices]IWebHostEnvironment environment,string folder)
        {
            try
            {
                var files = Request.Form.Files;
                //string contentRootPath = environment.ContentRootPath;//项目所在路径
                string webRootPath = environment.WebRootPath;wwwroot folder path where//
                string filePath = webRootPath + "/Uploads/Images/" + folder + "/";
                string fullPath = "";
                string uploadPath = "";

                foreach (var formFile in files)
                {
                    string fileName = Path.GetFileName(formFile.FileName);// 原始文件名称
                    string fileExtension = Path.GetExtension(fileName).ToLower(); // 文件扩展名
                    string saveName = DateTime.Now.ToString("yyyyMMddhhmmssffff") + fileExtension; // 保存文件名称
                    int filesize = int.Parse(formFile.Length.ToString()) / 1024;//图片大小（KB）
                    if (filesize > 5120 || filesize <= 2 || (fileExtension != ".jpg" && fileExtension != ".png" && fileExtension != ".gif"))
                    {
                        return Json(new { Success = false, Message = "upload failed! \ r Please upload jpg / png / gif format images, the file size should not exceed 5MB nor less than 2K " }); 
                    } 
                    fullPath = Path.Combine (filePath, SAVENAME);
                     IF (! Directory.Exists (filePath)) 
                    { 
                        Directory. CreateDirectory (filePath); 
                    } 
                    the using ( var Stream = new new the FileStream (fullPath, FileMode.CreateNew)) 
                    { 
                        formFile.CopyTo (Stream); 
                    } 
                    uploadPath = " / the Uploads / Images / " + folder + "/" + saveName;
                }

                return Json(new { Success = true, FilePath = uploadPath });
            }
            catch (Exception e)
            {
                NLogHelper.WriteDebug("图片上传方法异常："+ e.Message.ToString());
                return Json(new { Success = false, Message = e.Message.ToString() });
            }
           
        }

Front-end code:

        <tr>
            <th class="formTitle">导航图片</th>
            <td class="formValue" colspan="3">
                <input type="file" id="picture_upload" name="picture_upload" value='导航图片' />
            </td>
        </tr>

<link href="~/scripts/plugins/uploadify/uploadify.css" rel="stylesheet" />
<script src="~/scripts/plugins/uploadify/jquery.uploadify.js"></script>
<script type="text/javascript">
    $(document).ready(function () {
        $('#picture_upload').uploadify({
            uploader: '/Uploads/UploadImage?folder=ArticleCategory',
            swf: '/scripts/plugins/uploadify/uploadify.swf',
            buttonText: "请选择上传图片",
            height: 30,
            width: 120 ,
             // 'FileExt': '.. * .Jpg; * GIF, PNG *', // allow file format for upload .jpg *, * GIF, PNG *.. 
            // 'filedesc': 'Web Image files (.JPG, .GIF, .PNG) ', // filter out except * .jpg, * gif, * png file.. 
            // ' QueueID ':' fileQueue ', 
            ' the sizeLimit ' : ' 5.12 million ' ,                          / / maximum allowable file size 5M 
            // 'Auto': false, // need to submit an application manual 
            ' Multi ' : false ,                                  // once only allowed to upload a picture 
            ' onUploadSuccess ' :function(File, Data, Response) {
                 var obj = jQuery.parseJSON (Data); // the return of the object obj Json sequence into 
                IF (obj.success) { 
                    $ ( ' #PictureUrl ' ) .val (obj.filePath) ; 
                } 
                the else 
                    Alert (obj.Message); 
            } 
        }); 
    }); 

</ Script >