/// <summary>/// 为DataTable指定行中的生成缩略图/// </summary>/// <param name="dataTable">数据源</param>/// <param name="dataTableImageColumnName">要生成缩略图的数据源的列名</param>/// <param name="appendSmallPicColumnName">新增缩略图数据列的列名</param>/// <param name="imageFormat">源图像格式</param>/// <param name="maxWidth">图像自适应的最大宽度</param>/// <param name="maxHeight">最像自适应的最大高度</param>public static void GetSmallPic(DataTable dataTable, string dataTableImageColumnName, string appendSmallPicColumnName, ImageFormat imageFormat, int maxWidth, int maxHeight){var dc = new DataColumn(appendSmallPicColumnName, Type.GetType("System.Byte[]"));dataTable.Columns.Add(dc);for (int i = 0; i < dataTable.Rows.Count; i++){//生成缩略图GetSmallPic(dataTable.Rows[i], dataTableImageColumnName, appendSmallPicColumnName);var imageByte = (byte[])dataTable.Rows[i][dataTableImageColumnName];var ms = new MemoryStream(imageByte, 0, imageByte.Length);var sourceImage = Image.FromStream(ms);int newWidth, newHeight;ImageSelfAdaption(sourceImage, maxWidth, maxHeight, out newWidth, out newHeight);var myBitmap = new Bitmap(sourceImage, newWidth, newHeight);ms = new MemoryStream();myBitmap.Save(ms, imageFormat);dataTable.Rows[i][appendSmallPicColumnName] = ms.ToArray();ms.Close();}}/// <summary>/// 获取图像自适应后的宽高（设置最大宽高）/// </summary>/// <param name="image">图像</param>/// <param name="maxWidth">最大宽度</param>/// <param name="maxHeight">最大高度</param>/// <param name="newWidth">自适应后的图像宽度</param>/// <param name="newHeight">自适应后的图像高度</param>/// <returns></returns>public static void ImageSelfAdaption(Image image, int maxWidth, int maxHeight, out int newWidth, out int newHeight){var originalWidth = image.Width;var originalHeight = image.Height;double _newWidth = maxWidth, _newHeight = maxHeight;double t = originalWidth > maxWidth ? maxWidth : originalWidth;if (originalHeight * t / originalWidth > maxHeight){_newHeight = maxHeight;_newWidth = (double)maxHeight / originalHeight * originalWidth;}else{_newWidth = t;_newHeight = (t / originalWidth) * originalHeight;}newWidth = (int)_newWidth;newHeight = (int)_newHeight;}/// <summary>/// 获取补足透明区域的图像/// </summary>/// <param name="image">欲补足透明区域的图像</param>/// <param name="minComplementSize">补足透明区域的最小像素块大小（注：必须大于等于2）</param>/// <returns></returns>public static Bitmap GetComplementImage(Image image, int minComplementSize){if (minComplementSize < 2){return new Bitmap(image.Width, image.Height);}else{int newWidth = image.Width;int newHeight = image.Height;//宽度求余int width = image.Width % minComplementSize;//高度求余int height = image.Height % minComplementSize;//宽度不够if (width != 0){newWidth += minComplementSize - width;}if (height != 0) //高度不够
                {newHeight += minComplementSize - height;}return new Bitmap(image, newWidth, newHeight);}}/// <summary>/// 获取图像对象/// </summary>/// <param name="imageByte">图像二进制数据</param>/// <returns></returns>public static Image GetImage(byte[] imageByte){if (imageByte != null){var ms = new MemoryStream();ms.Write(imageByte, 0, imageByte.Length);return Image.FromStream(ms);}return null;}/// <summary>/// 获取图像二进制数据/// </summary>/// <param name="image">图像</param>/// <param name="imageFormat">图像格式</param>/// <returns></returns>public static byte[] GetImageByteArray(Image image, ImageFormat imageFormat){var ms = new MemoryStream();image.Save(ms, imageFormat);var img = new byte[ms.Length];ms.Position = 0;ms.Read(img, 0, Convert.ToInt32(ms.Length));ms.Close();return img;}