【话说有DBHper、IOHelper，可有ImgHelper？？？】

多收集一些常用的功能，然后看你是传入文件File还是传入文件名来处理，最后发布，保证推荐贴

我倒是有自己的dll不想分享了，分享出去过几次，帖子都不结。伤了

图片处理的内置类型就已經不错了。不过还可以进行一下封装。很简单，看看graphics类型就好了

有微软自己的webmatrix包里就集合了WebImage工具他就是你要的ImgHelper

AspJpeg dll 这个也可以

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;using YDSystem.ZXF.Config;namespace YDSystem.ZXF.Common.Configurable
{
    /// <summary>
    /// 图像处理帮助类
    /// </summary>
    public class ImageWorker
    {
        //会产生graphics异常的PixelFormat，索引颜色
        private static PixelFormat[] indexedPixelFormats = {
                                                               PixelFormat.Undefined,
                                                               PixelFormat.DontCare,
                                                               PixelFormat.Format16bppArgb1555,
                                                               PixelFormat.Format1bppIndexed,
                                                               PixelFormat.Format4bppIndexed,
                                                               PixelFormat.Format8bppIndexed
                                                           };        #region 私有方法
        /// <summary>
        /// 判断图片的PixelFormat 是否在引发异常的 PixelFormat 之中
        /// </summary>
        /// <param name="imgPixelFormat">原图片的PixelFormat</param>
        /// <returns></returns>
        private static bool IsIndexedPixelFormat(PixelFormat imgPixelFormat)
        {
            foreach (PixelFormat pf in indexedPixelFormats)
            {
                if (pf.Equals(imgPixelFormat)) return true;
            }
            return false;
        }        /// <summary>
        /// 计算水印的位置
        /// </summary>
        /// <param name="oWidth">源图片宽度</param>
        /// <param name="oHeight">源图片高度</param>
        /// <param name="Width">水印图片宽度</param>
        /// <param name="Height">鲨鱼图片高度</param>
        /// <returns></returns>
        private static PointF CountWaterPosition(YDSystem.ZXF.Config.WaterPosition position, int width, int height, int Width, int Height)
        {
            float padding = 15.0f;  //水印与图片边框间的距离            PointF point = new PointF();            //确定水印位置
            switch (position)
            {
                case WaterPosition.Center: //居中
                    point.X = (float)((width - Width) / 2);
                    point.Y = (float)((height - Height) / 2);
                    break;
                case WaterPosition.NorthEast: //右上
                    point.X = (float)(width - Width - padding);
                    point.Y = padding;
                    break;
                case WaterPosition.East: //右中
                    point.X = (float)(width - Width - padding);
                    point.Y = (float)((height - Height) / 2);
                    break;
                case WaterPosition.SouthEast: //右下
                    point.X = (float)(width - Width - padding);
                    point.Y = (float)(height - Height - padding);
                    break;
                case WaterPosition.South: //中下
                    point.X = (float)((width - Width) / 2);
                    point.Y = (float)(height - Height - padding);
                    break;
                case  WaterPosition.SouthWest: //左下
                    point.X = padding;
                    point.Y = (float)(height - Height - padding);
                    break;
                case WaterPosition.West: //左中
                    point.X = padding;
                    point.Y = (float)((height - Height) / 2);
                    break;
                case WaterPosition.NorthWest: //左上
                    point.X = padding;
                    point.Y = padding;
                    break;
                case WaterPosition.North: //中上
                    point.X = (float)((width - Width) / 2);
                    point.Y = padding;
                    break;
            }//switch            return point;
        }
        #endregion        /// <summary>
        /// 按指定的配置添加水印
        /// </summary>
        /// <param name="image">待添加水印的图片</param>
        /// <param name="config">指定的YDSystem.ZXF.Config.WaterConfigInfo水印配置实例</param>
        public static void AddWater(ref Image image, YDSystem.ZXF.Config.WaterConfigInfo config)
        {
            if (image == null)  //源图片不存在
            {
                return;
            }            int height = image.Height;  //原图片高度
            int width = image.Width;    //原图片宽度            if (IsIndexedPixelFormat(image.PixelFormat)) //索引色图片，必须转化为bitmap进行处理，否则会报异常
            {
                //创建bitmap对象
                Bitmap bmp = new Bitmap(width, height, PixelFormat.Format32bppArgb);
                Graphics gr = Graphics.FromImage(bmp);
                gr.InterpolationMode = InterpolationMode.HighQualityBicubic;
                gr.SmoothingMode = SmoothingMode.HighQuality;
                gr.CompositingQuality = CompositingQuality.HighQuality;
                //画到bitmap上
                gr.DrawImage(image, new Rectangle(0, 0, width, height), new Rectangle(0, 0, width, height), GraphicsUnit.Pixel);
                //复制
                image = (Image)bmp.Clone();
                //释放资源
                gr.Dispose();
                bmp.Dispose();
            }            //创建Graphics对象
            Graphics g = Graphics.FromImage(image);
            g.InterpolationMode = InterpolationMode.HighQualityBicubic;
            g.SmoothingMode = SmoothingMode.HighQuality;
            g.CompositingQuality = CompositingQuality.HighQuality;            PointF point = new PointF();    //水印位置            if (config.Type == WaterType.Text)  //水印类型是文字
            {
                //创建字体
                Font font = new Font(config.FontName, config.FontSize, config.FontStyle, GraphicsUnit.Pixel);                //测试字符串高度及宽度
                SizeF textSize = g.MeasureString(config.Text, font);                //保存字符串宽及高
                int Width = (int)textSize.Width;
                int Height = (int)textSize.Height;                //确定水印位置
                point = CountWaterPosition(config.Position, width, height, Width, Height);                //确定文本颜色
                Color color = Color.FromArgb(Convert.ToInt32(config.FontColor.Substring(1), 16));   //删除颜色#666666前面的“#”
                SolidBrush brush = new SolidBrush(Color.FromArgb(config.Opacity * 255 / 100, color));                //用白色brush画字符串阴影
                g.DrawString(config.Text, font, new SolidBrush(Color.White), point.X + 1, point.Y + 1);                //画出字符串
                g.DrawString(config.Text, font, brush, point);                //释放资源
                g.Dispose();            }//if
            else    //水印类型是图片
            {
                //获取水印图片
                Image Image = null;
                ImageAttributes attributes = new ImageAttributes();                try
                {
                    Image = Image.FromFile(Utils.MapPath(config.ImagePath));                    //获取水印图片宽和高
                    int Width = Image.Width;
                    int Height = Image.Height;                    //确定水印位置
                    point = CountWaterPosition(config.Position, width, height, Width, Height);                    //透明水印
                    float[][] colorMatrixParam = {
                                                   new float[] {1.0f,0.0f,0.0f,0.0f,0.0f},
                                                   new float[] {0.0f,1.0f,0.0f,0.0f,0.0f},
                                                   new float[] {0.0f,0.0f,1.0f,0.0f,0.0f},
                                                   new float[] {0.0f,0.0f,0.0f,config.Opacity * 1.0f / 100,0.0f},  //透明度
                                                   new float[] {0.0f,0.0f,0.0f,0.0f,1.0f}
                                                 };                    ColorMatrix colorMatrix = new ColorMatrix(colorMatrixParam);                    //重设图像属性
                    attributes.SetColorMatrix(colorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);                    //铬上水印
                    g.DrawImage(Image, new Rectangle((int)point.X, (int)point.Y, Width, Height), 0, 0, Width, Height, GraphicsUnit.Pixel, attributes);
                }
                catch (Exception ex)
                {
                    Utils.ShowAdminError("水印图片不存在", ex.Message);
                }
                finally
                {
                    //释放资源
                    attributes.Dispose();
                    Image.Dispose();
                    g.Dispose();
                }            }//else
        }        /// <summary>
        /// 按默认的水印配置添加水印
        /// </summary>
        /// <param name="image">待添加水印的图片实例</param>
        public static void AddDefaultWater(ref Image image)
        {
            AddWater(ref image, GlobalConfigManage.LoadConfig().WaterSettings);
        }        /// <summary>
        /// 按默认的水印配置添加水印
        /// </summary>
        /// <param name="image">待添加水印的图片实例</param>
        public static void AddArticleWater(ref Image image)
        {
            WaterConfigInfo config = null;
            if (GlobalConfigManage.LoadConfig().UseDefaultWaterFirst) //默认配置优先
            {
                config = GlobalConfigManage.LoadConfig().WaterSettings;
            }
            else
            {
                config = ArticleConfigManage.LoadConfig().WaterSettings;
            }
            AddWater(ref image, config);
        }

        /// <summary>
        /// 生成指定大小的缩略图（不变形），保存成jpg的格式。若原图尺寸比要求的缩略图小，无法生成。
        /// </summary>
        /// <param name="image"></param>
        /// <param name="absSavedPath">保存缩略图完整的绝对路径，包括文件名</param>
        /// <param name="width">缩略图宽</param>
        /// <param name="height">缩略图高</param>
        /// <returns></returns>
        public static bool MakeThumbnail(Image image, string absSavedPath, int width, int height)
        {
            #region 原方法，按配置文件中的配置大小生成缩略图
            ////获取缩略图设置
            //int sWidth = GetInt("MaxThumbnailWidth");
            //int sHeight = GetInt("MaxThumbnailHeight");
            //bool isCutMode = Convert.ToBoolean(GetString("IsCutMode"));            ////缩略图尺寸不能超过原图尺寸
            //if(sWidth > oWidth)
            //{
            //    sWidth  = oWidth;
            //}
            //if(sHeight > oHeight)
            //{
            //    sHeight = oHeight;
            //}
            ////计算缩略图应有的尺寸
            //int width = 0;
            //int height = 0;            //int x = 0;
            //int y = 0;
            //if (isCutMode)  //裁剪模式
            //{
            //    //裁剪原图片的中部
            //    x = (oWidth - sWidth) / 2;
            //    y = (oHeight - sHeight ) / 2;
            //    //图片尺寸
            //    width = sWidth;
            //    height = sHeight;
            //    //调整原图的裁剪大小
            //    oWidth = sWidth;
            //    oHeight = sHeight;
            //}
            //else    //全图模式
            //{
            //    if (oWidth * 1.0 / sWidth > oHeight * 1.0 / sHeight)    //宽的比例比高的大，要以sWidth为准
            //    {
            //        width = sWidth;
            //        //按原图比例转换高度
            //        height = (int)(width * oHeight * 1.0 / oWidth);
            //    }
            //    else    //高的比例大
            //    {
            //        height = sHeight;
            //        //按原图比例转换宽度
            //        width = (int)(height * oWidth * 1.0 / oHeight);
            //    }
            //}
            #endregion            //获取原图尺寸
            int oWidth = image.Width;
            int oHeight = image.Height;            //检查缩略图与原图的尺寸
            if (width <= 0 || height <= 0 || oWidth < width || oHeight < height)  //尺寸不符，无法生成缩略图
            {
                return false;
            }            //先把原图缩小到可获取缩略图的最小尺寸
            int minWidth;   //最小宽
            int minHeight;  //最小高            //根据原图与缩略图的宽高比例决定最小图的尺寸（原图宽/缩略图宽原图高/缩略图高）
            if (oWidth * 1.0 / width > oHeight * 1.0 / height)  //宽的比例大，以缩略图的高为基准生成最小图
            {
                minHeight = height;
                minWidth = (int)(oWidth * 1.0 / oHeight * minHeight);  //按原比例缩小
            }
            else    //高的比例大，以缩略图的宽为基准生成最小图
            {
                minWidth = width;
                minHeight = (int)(oHeight * 1.0 / oWidth * minWidth);
            }            Graphics g = null;            //根据计算的尺寸生成最小图
            Bitmap minBmp = new Bitmap(minWidth, minHeight);            g = Graphics.FromImage(minBmp);
            //设置高质量插值法
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;            //设置高质量,低速度呈现平滑程度
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //设置合成模式
            g.CompositingQuality = CompositingQuality.HighQuality;            g.Clear(Color.Transparent);            g.DrawImage(image, new Rectangle(0, 0, minWidth, minHeight), new Rectangle(0, 0, oWidth, oHeight), GraphicsUnit.Pixel);
            int x = 0;  //缩略图左上角x坐标
            int y = 0;  //缩略图左上角y坐标
            //计算左上角坐标
            if (minWidth > width)   //最小图比缩略图宽
            {
                x = (int)((minWidth - width) * 1.0 / 2);
            }
            if (minHeight > height)
            {
                y = (int)((minHeight - height) * 1.0 / 2);
            }            //创建bitmap
            Bitmap bmp = new Bitmap(width, height);
            g = Graphics.FromImage(bmp);            //设置高质量插值法
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;            //设置高质量,低速度呈现平滑程度
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //设置合成模式
            g.CompositingQuality = CompositingQuality.HighQuality;            //清空画布并以透明背景色填充
            g.Clear(Color.Transparent);            //裁剪缩略图
            g.DrawImage(minBmp, new Rectangle(0, 0, width, height), new Rectangle(x, y, width, height), GraphicsUnit.Pixel);
            try
            {
                //从配置文件中获取图片品质系数
                long quality = GlobalConfigManage.LoadConfig().ImageSettings.Quality;                ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
                ImageCodecInfo ici = null;
                foreach (ImageCodecInfo codec in codecs)
                {
                    if (codec.MimeType == "image/jpeg")
                    {
                        ici = codec;
                        break;
                    }
                }
                EncoderParameters ep = new EncoderParameters();
                ep.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);                //以JPEG格式保存，图像质量较好
                bmp.Save(absSavedPath, ici, ep);
            }
            catch (Exception ex)
            {
                //向外抛出异常
                return false;
                throw ex;            }
            finally
            {
                minBmp.Dispose();
                g.Dispose();
                bmp.Dispose();
            }            return true;
        }        /// <summary>
        /// 生成指定大小的缩略图（不变形），保存成jpg的格式。如果原图比要求的缩略图小，不做任何操作。
        /// </summary>
        /// <param name="srcPath"></param>
        /// <param name="savePath"></param>
        public static bool MakeThumbnail(string absSrcPath, string absSavedPath, int width, int height)
        {
            Image image;
            try
            {
                image = Image.FromFile(absSrcPath);
            }
            catch (Exception ex)
            {
                return false;
                throw ex;
            }
            bool result = MakeThumbnail(image, absSavedPath, width, height);
            //销毁对象,释放资源
            image.Dispose();
            return result;
        }        /// <summary>
        /// 等比例缩放图片，保存成jpg的格式，约束最大宽度和最大高度
        /// </summary>
        /// <param name="image"></param>
        /// <param name="savePath"></param>
        /// <param name="maxHeight"></param>
        /// <param name="maxWidth"></param>
        public static void ZoomImage(Image image, string savePath, int maxWidth, int maxHeight)
        {
            //获取原图尺寸
            int oWidth = image.Width;
            int oHeight = image.Height;            //缩略图尺寸不能超过原图尺寸
            if (maxWidth > oWidth)
            {
                maxWidth = oWidth;
            }
            if (maxHeight > oHeight)
            {
                maxHeight = oHeight;
            }            //计算缩略图应有的尺寸
            int width = 0;
            int height = 0;            if (oWidth * 1.0 / maxWidth > oHeight * 1.0 / maxHeight)    //宽的比例比高的大，要以maxWidth为准
            {
                width = maxWidth;
                //按原图比例转换高度
                height = (int)(width * oHeight * 1.0 / oWidth);
            }
            else    //高的比例大
            {
                height = maxHeight;
                //按原图比例转换宽度
                width = (int)(height * oWidth * 1.0 / oHeight);
            }            //创建bitmap
            Bitmap bmp = new Bitmap(width, height);
            Graphics g = Graphics.FromImage(bmp);            //设置高质量插值法
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;            //设置高质量,低速度呈现平滑程度
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            //清空画布并以透明背景色填充
            g.Clear(Color.Transparent);            g.DrawImage(image, new Rectangle(0, 0, width, height), new Rectangle(0, 0, oWidth, oHeight), GraphicsUnit.Pixel);            try
            {
                //从配置文件中获取图片品质系数
                long quality = GlobalConfigManage.LoadConfig().ImageSettings.Quality;                ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
                ImageCodecInfo ici = null;
                foreach (ImageCodecInfo codec in codecs)
                {
                    if (codec.MimeType == "image/jpeg")
                    {
                        ici = codec;
                        break;
                    }
                }
                EncoderParameters ep = new EncoderParameters();
                ep.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);                //以JPEG格式保存，图像质量较好
                bmp.Save(savePath, ici, ep);
            }
            catch (Exception ex)
            {
                //向外抛出异常
                throw ex;
            }
            finally
            {
                g.Dispose();
                bmp.Dispose();
            }
        }        /// <summary>
        /// 生成缩略图并保存
        /// </summary>
        /// <param name="srcPath">源图片的完整物理路径</param>
        /// <param name="savePath">目标图片的完整物理路径</param>
        /// <param name="maxWidth">最大宽度</param>
        /// <param name="maxHeight">最大高度</param>
        public static void ZoomImage(string srcPath, string savePath, int maxWidth, int maxHeight)
        {
            Image image = Image.FromFile(srcPath);
            ZoomImage(image, savePath, maxWidth, maxHeight);
            //销毁对象,释放资源
            image.Dispose();
        }
    }
}
不懂地方，欢迎追问

看这个 System.Web.Helpers.WebImage：http://msdn.microsoft.com/en-us/library/system.web.helpers.webimage(v=vs.111).aspx

调试易

【话说有DBHper、IOHelper，可有ImgHelper？？？】

解决方案 »