C# Web如何实现文件上传的示例详解

        [HttpPost]
        [Route("Common/uploadFile1")]
        public string uploads()
        {
            HttpContextBase context = (HttpContextBase)Request.Properties["MS_HttpContext"];//获取传统context
            HttpRequestBase request = context.Request;//定义传统request对象
            HttpFileCollectionBase files = request.Files;
            string fileSuffix = Path.GetExtension(files[0].FileName).ToLower();
            string fileId = Guid.NewGuid().ToString();
            string dateKey = DateTime.Now.ToString("yyyyMMdd");
            string savaPath, uri;     
            uri = @"/fileData/rest/" + dateKey + @"/";
            savaPath = request.MapPath(uri);
            if (!Directory.Exists(savaPath))
            {
                Directory.CreateDirectory(savaPath);
            }
            try
            {
                files[0].SaveAs(savaPath + fileId + fileSuffix);
                return uri + fileId + fileSuffix;
            }catch (Exception ex){
                return ex.Message;
            }
        }

        /// <summary>
        /// 通用文件上传接口
        /// </summary>
        /// <param name="file"></param>
        /// <returns></returns>
        [HttpPost]
        [Route("Common/uploadFile2")]
        public  async Task<Axios<string>>  upload(IFormFile file)
        {
            string fileSuffix = Path.GetExtension(file.FileName).ToLower();
            string fileId = Guid.NewGuid().ToString();
            string dateKey = DateTime.Now.ToString("yyyyMMdd");
            string savaPath,uri;
            uri = @"/fileData/rest/"  + dateKey  + @"/";
            savaPath =  Path.Combine(Directory.GetCurrentDirectory(), uri);
            if (!Directory.Exists(savaPath)){Directory.CreateDirectory(savaPath);}
            //创建特定名称的文件流
            await using var stream = new FileStream(savaPath + fileId + fileSuffix, FileMode.Create);
            try
            {
                //上传文件
                await file.CopyToAsync(stream);
                stream.Flush();
                return Axios<string>.ok(uri + fileId + fileSuffix);
            } catch (Exception ex)  {
                //上传异常处理 
                return Axios<string>.fail(ex.Message);
            }

        [HttpPost]
        public JsonResult uploadX(HttpPostedFileBase file)
        {
            String suffix = file.FileName.Substring(file.FileName.LastIndexOf(".", StringComparison.Ordinal));
            string fileName = Guid.NewGuid().ToString().Replace("-", "") + suffix;
            string uri = string.Format("{0}/{1}/{2}/", "fileData", "rest", DateTime.Now.Year+""+DateTime.Now.Month +""+ DateTime.Now.Day);
            string filePath = Server.MapPath(string.Format("~/{0}",uri));
            if (!Directory.Exists(filePath))
            {
                Directory.CreateDirectory(filePath);
            }
            file.SaveAs(Path.Combine(filePath, fileName));
            return Json(uri + fileName);
        }