Erstellen Sie ein avatar-upload-Formular für Benutzer

können Sie diese Klasse verwenden, für den Sie eine Datei Hochladen zum server :

public static class FileUpload
{
        public static char DirSeparator = System.IO.Path.DirectorySeparatorChar;
        public static string FilesPath = HttpContext.Current.Server.MapPath("~\\Content" + DirSeparator + "Uploads" + DirSeparator);

        public static string UploadFile(HttpPostedFileBase file)
        {
            //Check if we have a file
            if (null == file) return "";
            //Make sure the file has content
            if (!(file.ContentLength > 0)) return "";

            string fileName =DateTime.Now.Millisecond+ file.FileName;
            string fileExt = Path.GetExtension(file.FileName);

            //Make sure we were able to determine a proper extension
            if (null == fileExt) return "";

            //Check if the directory we are saving to exists
            if (!Directory.Exists(FilesPath))
            {
                //If it doesn't exist, create the directory
                Directory.CreateDirectory(FilesPath);
            }

            //Set our full path for saving
            string path = FilesPath + DirSeparator + fileName;

            //Save our file
            file.SaveAs(Path.GetFullPath(path));

            //Save our thumbnail as well
            ResizeImage(file, 70, 70);

            //Return the filename
            return fileName;
        }

        public static void DeleteFile(string fileName)
        {
            //Don't do anything if there is no name
            if (fileName.Length == 0) return;

            //Set our full path for deleting
            string path = FilesPath + DirSeparator + fileName;
            string thumbPath = FilesPath + DirSeparator + "Thumbnails" + DirSeparator + fileName;

            RemoveFile(path);
            RemoveFile(thumbPath);
        }

        private static void RemoveFile(string path)
        {
            //Check if our file exists
            if (File.Exists(Path.GetFullPath(path)))
            {
                //Delete our file
                File.Delete(Path.GetFullPath(path));
            }
        }

        public static void ResizeImage(HttpPostedFileBase file, int width, int height)
        {
            string thumbnailDirectory = String.Format(@"{0}{1}{2}", FilesPath, DirSeparator, "Thumbnails");

            //Check if the directory we are saving to exists
            if (!Directory.Exists(thumbnailDirectory))
            {
                //If it doesn't exist, create the directory
                Directory.CreateDirectory(thumbnailDirectory);
            }

            //Final path we will save our thumbnail
            string imagePath = String.Format(@"{0}{1}{2}", thumbnailDirectory, DirSeparator, file.FileName);
            //Create a stream to save the file to when we're done resizing
            FileStream stream = new FileStream(Path.GetFullPath(imagePath), FileMode.OpenOrCreate);

            //Convert our uploaded file to an image
            Image OrigImage = Image.FromStream(file.InputStream);
            //Create a new bitmap with the size of our thumbnail
            Bitmap TempBitmap = new Bitmap(width, height);

            //Create a new image that contains are quality information
            Graphics NewImage = Graphics.FromImage(TempBitmap);
            NewImage.CompositingQuality = CompositingQuality.HighQuality;
            NewImage.SmoothingMode = SmoothingMode.HighQuality;
            NewImage.InterpolationMode = InterpolationMode.HighQualityBicubic;

            //Create a rectangle and draw the image
            Rectangle imageRectangle = new Rectangle(0, 0, width, height);
            NewImage.DrawImage(OrigImage, imageRectangle);

            //Save the final file
            TempBitmap.Save(stream, OrigImage.RawFormat);

            //Clean up the resources
            NewImage.Dispose();
            TempBitmap.Dispose();
            OrigImage.Dispose();
            stream.Close();
            stream.Dispose();
        }

}

können Sie auch speichern Sie die Miniaturansicht Ihrer Fotos mit ResizeImage Methode und In der Steuerung werde ich speichern Sie die Datei Namen in der Datenbank auf diese Weise:

[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult Create(User user, HttpPostedFileBase file)
{

                //TODO: Add insert logic here
            user.Pictuer = FileUpload.UploadFile(file);
                    db.User.Add(user);
                    db.SaveChanges();
                    return RedirectToAction("Index");


 }

auch für konvertieren hochgeladenen Bilder, die Sie verwenden können, dieser code innen UploadFile Methode :

    System.Drawing.Image image1 = System.Drawing.Image.FromFile(@"C:\test.bmp");
//Save the image in JPEG format.
        image1.Save(@"C:\test.jpg", System.Drawing.Imaging.ImageFormat.Jpeg);

        //Save the image in GIF format.
        image1.Save(@"C:\test.gif", System.Drawing.Imaging.ImageFormat.Gif);

        //Save the image in PNG format.
        image1.Save(@"C:\test.png", System.Drawing.Imaging.ImageFormat.Png);