.net 上传文件

Controller层接收文件 参数     [FromServices] IHostingEnvironment env 

 public IActionResult UploadFile([FromServices] IHostingEnvironment env)
        {
            var result = new APIResult<int>();
            try
            {
                var file = HttpContext.Request.Form.Files[0];
                _documentService.UploadFiles(env, file);

            }
            catch (Exception)
            {
                result.ReturnCode = ReturnCode.SysException;
                result.Message = "系统错误";
            }
            return Json(result);
        }

用一个变量File接收文件信息   

var file = HttpContext.Request.Form.Files[0];

public void UploadFiles(IHostingEnvironment env, IFormFile file)
        {
            var filePath = env.WebRootPath;  //获取路径
            var fileName = file.FileName;    //获取文件名称
            var ext = Path.GetExtension(file.FileName);  //获取上传文件后缀名
            var url = filePath + @"UploadDocuments";
            if (!Directory.Exists(url))   //(字符串存在路径)确定给定路径是否引用磁盘上的现有目录。
            {
                Directory.CreateDirectory(url); //创建指定路径中的所有目录和子目录，除非它们已经存在。
            }
            var path = filePath + @"UploadDocuments" + DateTime.UtcNow.ToString("yyyyMMddhhmmssfff") + ext;using (var fStream = new FileStream(path, FileMode.CreateNew, FileAccess.ReadWrite)) //添加文件成功
                {
                        //File.Delete(PathName);   //删除指定目录文件
                }
            }
        }