郑德才博客

        //参数说明
        //FileBox:上传表单中的表单名
        //SavePath:保存路径
        //ThumbnailWidth:略缩图宽
        //ThumbnailHeight:略缩图高
        //FilePath:文件保存路径（输出参数）
        //FileName:文件名称（输出参数）
        //LastError:（输出错误）
        public static bool UploadImages(System.Web.UI.HtmlControls.HtmlInputFile FileBox, string SavePath, Int32 ThumbnailWidth, Int32 ThumbnailHeight, out   String FilePath, out   String FileName, out   string LastError)
        {
            DateTime datTime = System.DateTime.Now;
            String strTemp;
            string strFileName = FileBox.PostedFile.FileName;
            bool blnResult;
            LastError = " ";
            System.Drawing.Image xImage;
            System.Drawing.Bitmap xBitmap;
            int PhotoHeight, PhotoWidth;
            string BasePath = System.Web.HttpContext.Current.Server.MapPath("../ ");
            Rectangle NewPhoto;
            System.Drawing.Imaging.ImageFormat xObject;
            string Extension = " ";
            FileName = " ";
            FilePath = " ";

            try
            {
                if (strFileName == " ")
                {
                    LastError = "请点击浏览选择要上传的文件! ";
                    return false;
                }
                if (Convert.ToDecimal(FileBox.PostedFile.ContentLength) <= 2000000 && Convert.ToDecimal(FileBox.PostedFile.ContentLength) > 1500)
                {
                    //查看扩展名是否合法
                    Extension = Path.GetExtension(strFileName);
                    Extension = Extension.ToLower();
                    if (Extension == ".gif " || Extension == ".jpg " || Extension == ".jpeg " || Extension == ".bmp ")
                    {
                        switch (Extension)
                        {
                            case ".gif ":
                                xObject = System.Drawing.Imaging.ImageFormat.Gif;
                                break;
                            case ".bmp ":
                                xObject = System.Drawing.Imaging.ImageFormat.Bmp;
                                break;
                            default:
                                xObject = System.Drawing.Imaging.ImageFormat.Jpeg;

                                break;
                        }
                    }
                    else
                    {
                        LastError = "上传的文件不是有效的图片文件，请上传格式为：.gif.jpg.bmp的文件！ ";
                        return false;
                    }
                    //-----------------------------
                    //生成保存的文件路径及文件名
                    //-----------------------------
                    strTemp = datTime.ToShortDateString().Replace("- ", " ");
                    FileName = datTime.ToLongTimeString().Replace(": ", " ") + Extension;
                    FilePath = SavePath + strTemp + "/ ";
                    Friendlib.Function.CreateDirectory(BasePath + FilePath);
                    //保存大图
                    xImage = System.Drawing.Bitmap.FromStream(FileBox.PostedFile.InputStream);

                    xImage.Save(BasePath + FilePath + FileName);
                    xImage.Dispose();
                    //-----------------------------
                    //开始生成缩略图
                    //-----------------------------
                    xBitmap = new Bitmap(BasePath + FilePath + FileName);//------------------

                    PhotoHeight = xBitmap.Height;
                    PhotoWidth = xBitmap.Width;
                    //判断图片的形状  
                    if (Convert.ToDecimal(PhotoHeight) / Convert.ToDecimal(PhotoWidth) > Convert.ToDecimal(ThumbnailHeight) / Convert.ToDecimal(ThumbnailWidth))//高有余  
                    {
                        PhotoHeight = Convert.ToInt16((Convert.ToDecimal(ThumbnailHeight) / Convert.ToDecimal(ThumbnailWidth)) * Convert.ToDecimal(PhotoWidth));
                        NewPhoto = new Rectangle(0, 0, PhotoWidth, PhotoHeight);
                    }
                    else if (Convert.ToDecimal(PhotoHeight) / Convert.ToDecimal(PhotoWidth) < Convert.ToDecimal(ThumbnailHeight) / Convert.ToDecimal(ThumbnailWidth))
                    {
                        PhotoWidth = Convert.ToInt16((Convert.ToDecimal(ThumbnailWidth) / Convert.ToDecimal(ThumbnailHeight)) * Convert.ToDecimal(PhotoHeight));
                        NewPhoto = new
                        Rectangle(Convert.ToInt16((Convert.ToDecimal(xBitmap.Width) - Convert.ToDecimal(PhotoWidth)) / 2), 0, PhotoWidth, PhotoHeight);
                    }
                    else
                    {
                        NewPhoto = newRectangle(0, 0, PhotoWidth, PhotoHeight);
                    }
                    System.Drawing.Image myBitmap;
                    myBitmap = xBitmap.Clone(NewPhoto, System.Drawing.Imaging.PixelFormat.DontCare);
                    System.Drawing.Image.GetThumbnailImageAbort myCallback = new
                    System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback);
                    System.Drawing.Image myThumbnail =
                    myBitmap.GetThumbnailImage(ThumbnailWidth, ThumbnailHeight, myCallback,
                    IntPtr.Zero); myThumbnail.Save(BasePath + FilePath + "s " + FileName, xObject);
                    myThumbnail.Dispose(); myBitmap.Dispose(); xBitmap.Dispose(); return true;
                }
                else
                {
                    blnResult = false; LastError = "不能上传大于2M及小于1.5K的图片! ";
                }
            }
            catch (Exception ex)
            {
                throw new System.Exception((ex.Message + ("\r\n " + ex.StackTrace)));
            }
            return blnResult;
        }
        private static bool ThumbnailCallback() { return false; }