在 ASP.NET 上保存发布的图像文件错误

Question

所以，我想上传一个图像文件并将其保存到某个路径。它在第一次尝试时有效，但如果要第二次上传它，即使我关闭应用程序并再次运行它，它也会出错

The process cannot access the file '..mypath..' because it is being used by another process

我该如何解决这个问题？

这是我的代码

public ActionResult UploadImage(HttpPostedFileBase file, string text)
    {
        if (file != null && file.ContentLength > 0)
        {
            var fileName = datetime + "_" + Path.GetFileName(file.FileName);

            log_file = fileName;
            var path = Path.Combine(Server.MapPath("~/Images/"), fileName);
            file.SaveAs(path); //error

            Bitmap bmp = new Bitmap(path);

            bmp = EmbedText(bmp, "Some Text");

            var outputFileName = Path.Combine(Server.MapPath("~/StegoImages/"), fileName); ;
            using (MemoryStream memory = new MemoryStream())
            {
                using (FileStream fs = new FileStream(outputFileName, FileMode.Create, FileAccess.ReadWrite))
                {
                    bmp.Save(memory, ImageFormat.Png);
                    byte[] bytes = memory.ToArray();
                    fs.Write(bytes, 0, bytes.Length);
                }
            }

            string coba = extractText(bmp);
        }
        else
        {
            TempData["flag_no_file"] = '1';
            return RedirectToAction("UploadImage");
        }
        return View();
    }

有人可以帮助我吗？可能是我上传图片的代码不对，怎么办呢？

我正在使用 C# asp .net mvc

对不起我的英语..

Answer 1

我想知道您如何调用此 API 请求。 但是试试这段代码。图片在此处在请求正文中发送。

 [HttpPost]        
 public HttpResponseMessage UploadJsonFile()
 {        
                userID = "any name";    
                    HttpResponseMessage response = new HttpResponseMessage();
                    var httpRequest = HttpContext.Current.Request;
                    if (httpRequest.Files.Count > 0)
                    {
                        foreach (string file in httpRequest.Files)
                        {
                            try
                            {
                                var postedFile = httpRequest.Files[file];
                                var filePath = HttpContext.Current.Server.MapPath("~/ProfileImages/"+ userID);
                                if (!Directory.Exists(filePath))
                                {
                                    Directory.CreateDirectory(filePath);
                                }
                                else
                                {
                                    DirectoryInfo directory = new DirectoryInfo(filePath);
                                    FileInfo[] files = directory.GetFiles("*.jpg");
                                    foreach (FileInfo fil in directory.GetFiles())
                                    {
                                        fil.Delete(); //Delete existing image...
                                    }
                                }
                                Random rnd = new Random();
                                int num = rnd.Next(1, 100);
                                postedFile.SaveAs(filePath +"/"+ num+postedFile.FileName);
                            }
                            catch (Exception e)
                            {
                                ExceptionLogging.SendErrorToText(e);
                            }
                        }
                    }
                    return response;
                }

Answer 2

再读一遍那篇文章，它会对你有所帮助。

How save uploaded file? c# mvc

另外，请确保您的存档名称不存在并且任何软件都不会使用它。

var fileName = datetime + "_" + Path.GetFileName(file.FileName);

检查此行和服务器路径。