namespace EntityFrameworks.Application.Core.FileUpload { /// <summary> /// 图像上传功能的实现 /// </summary> public class UploadImpl { public UploadImpl(IFileUploadSize fileUploadSize) { _fileUploadSize = fileUploadSize ?? new TestFileUploadSize(); } public UploadImpl() : this(null) { } #region Fields & Consts static string FileHostUri = System.Configuration.ConfigurationManager.AppSettings["FileHostUri"] ?? HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Authority; Point point = new Point(0, 0); //图像从那个坐标点进行截取 double wRate = 1, hRate = 1, setRate = 1; int newWidth = 0, newHeight = 0; IFileUploadSize _fileUploadSize; #endregion #region 图像缩放 /// <summary> /// 图像的缩放 /// </summary> /// <param>缩放文件</param> /// <param>宽</param> /// <param>高</param> /// <param>是否等比例缩放</param> /// <param>缩放后存放的地址</param> /// <returns></returns> bool CreateThumbnail(HttpPostedFile file, ImageSize imageSize, bool isEqualScale, string name) { double width = (double)imageSize.Width; double height = (double)imageSize.Height; ; try { System.Drawing.Image image = System.Drawing.Image.FromStream(file.InputStream); if (isEqualScale) { if (image.Height > height) { hRate = height / image.Height; } if (image.Width > width) { wRate = width / image.Width; } if (wRate != 1 || hRate != 1) { if (wRate > hRate) { setRate = hRate; } else { setRate = wRate; } } newWidth = (int)(image.Width * setRate); newHeight = (int)(image.Height * setRate); if (height > newHeight) { point.Y = Convert.ToInt32(height / 2 - newHeight / 2); } if (width > newWidth) { point.X = Convert.ToInt32(width / 2 - newWidth / 2); } } Bitmap bit = new Bitmap((int)(width), (int)(height)); Rectangle r = new Rectangle(point.X, point.Y, (int)(image.Width * setRate), (int)(image.Height * setRate)); Graphics g = Graphics.FromImage(bit); g.Clear(Color.White); g.DrawImage(image, r); MemoryStream ms = new MemoryStream(); bit.Save(ms, ImageFormat.Jpeg); byte[] bytes = ms.ToArray(); string fileName = name + imageSize.ToString();//为缩放图像重新命名 using (FileStream stream = new FileStream(fileName, FileMode.Create, FileAccess.Write)) { stream.Write(bytes, 0, bytes.Length); } bit.Dispose(); ms.Dispose(); image.Dispose(); return true; } catch (Exception) { return false; } } /// <summary> /// 图像的等比例缩放,默认文件名不改变，会将原文件覆盖 /// </summary> /// <param></param> /// <param></param> /// <param></param> /// <returns></returns> bool CreateThumbnail(HttpPostedFile file, ImageSize imageSize, string name) { return CreateThumbnail(file, imageSize, true, name); } #endregion public string Upload(HttpContext context, UpLoadType type, bool isScale) { ImageSize imageSize = _fileUploadSize.ImageSizeForType[type]; HttpFileCollection files = context.Request.Files; if (files.Count == 0) { throw new ArgumentNullException("please choose file for upload."); } string path = "/upload/" + type.ToString();//相对路径 if (!Directory.Exists(path)) Directory.CreateDirectory(path); // 只取第 1 个文件 var file = files[0]; if (file != null && file.ContentLength > 0) { try { string filename = context.Request.Form["fileName"].Split('.')[0] + "_" + DateTime.Now.ToString("yyyyMMddhhssmm") + imageSize.ToString(); // 本地文件系统路径 string savePath = Path.Combine(context.Server.MapPath(path), filename); file.SaveAs(savePath); if (isScale) CreateThumbnail(file, imageSize, savePath); //返回URI路径 string ImageUri = FileHostUri + path + "https://www.jb51.net/" + filename; return "1|" + ImageUri; } catch (Exception ex) { return "0|" + ex.Message; } } return null; } } }
效果图：
为大家推荐一个专题，供大家学习：《ASP.NET文件上传汇总》
以上就是关于ASP.NET文件上传控件Uploadify的第一部分内容介绍，接下来还有更新，希望大家不要错过。
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