C#图片处理基本应用(裁剪,缩放,清晰度,水印)

代码

封装了几个通用的方法，如发现有BUG或漏洞还请及时指正。

using System;

using System.Collections.Generic;

using System.Text;

using System.IO;

using System.Drawing;

using System.Drawing.Drawing2D;

using System.Drawing.Imaging;

namespaceWuJian.Common

{

    /// <summary>

    /// 图片处理类

    /// 吴剑 2008-07-02 创建

    /// 吴剑 2011-01-21 修改

    /// </summary>

    publicclass PTImage

    {

        #region 正方型裁剪并缩放

        /// <summary>

        /// 正方型裁剪

        /// 以图片中心为轴心，截取正方型，然后等比缩放

        /// 用于头像处理

        /// </summary>

        /// <remarks>吴剑 2010-11-23</remarks>

        /// <param name="postedFile">原图HttpPostedFile对象</param>

        /// <param name="fileSaveUrl">缩略图存放地址</param>

        /// <param name="side">指定的边长（正方型）</param>

        /// <param name="quality">质量（范围0-100）</param>

        public staticvoid CutForSquare(System.Web.HttpPostedFile postedFile,string fileSaveUrl,int side, int quality)

        {

            //创建目录

            string dir = Path.GetDirectoryName(fileSaveUrl);

            if (!Directory.Exists(dir))

               Directory.CreateDirectory(dir);

            //原始图片（获取原始图片创建对象，并使用流中嵌入的颜色管理信息）

            System.Drawing.Image initImage = System.Drawing.Image.FromStream(postedFile.InputStream,true);

            //原图宽高均小于模版，不作处理，直接保存

            if (initImage.Width <= side && initImage.Height <= side)

            {

               initImage.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);

            }

            else

            {

               //原始图片的宽、高

               int initWidth = initImage.Width;

               int initHeight = initImage.Height;

               //非正方型先裁剪为正方型

               if (initWidth != initHeight)

               {

                   //截图对象

                   System.Drawing.Image pickedImage = null;

                   System.Drawing.Graphics pickedG = null;

                   //宽大于高的横图

                   if (initWidth > initHeight)

                   {

                       //对象实例化

                       pickedImage = newSystem.Drawing.Bitmap(initHeight, initHeight);

                       pickedG = System.Drawing.Graphics.FromImage(pickedImage);

                       //设置质量

                       pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

                       pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                       //定位

                       Rectangle fromR = newRectangle((initWidth - initHeight) / 2, 0, initHeight, initHeight);

                       Rectangle toR = newRectangle(0, 0, initHeight, initHeight);

                       //画图

                       pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);

                       //重置宽

                       initWidth = initHeight;

                   }

                   //高大于宽的竖图

                   else

                   {

                       //对象实例化

                       pickedImage = newSystem.Drawing.Bitmap(initWidth, initWidth);

                       pickedG = System.Drawing.Graphics.FromImage(pickedImage);

                       //设置质量

                       pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

                       pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                       //定位

                       Rectangle fromR = newRectangle(0, (initHeight - initWidth) / 2, initWidth, initWidth);

                       Rectangle toR = newRectangle(0, 0, initWidth, initWidth);

                       //画图

                       pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);

                       //重置高

                       initHeight = initWidth;

                   }

                   //将截图对象赋给原图

                   initImage = (System.Drawing.Image)pickedImage.Clone();

                   //释放截图资源

                   pickedG.Dispose();

                   pickedImage.Dispose();

               }

               //缩略图对象

               System.Drawing.Image resultImage = newSystem.Drawing.Bitmap(side, side);

               System.Drawing.Graphics resultG = System.Drawing.Graphics.FromImage(resultImage);

               //设置质量

               resultG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

               resultG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

               //用指定背景色清空画布

               resultG.Clear(Color.White);

               //绘制缩略图

               resultG.DrawImage(initImage, newSystem.Drawing.Rectangle(0, 0, side, side), newSystem.Drawing.Rectangle(0, 0, initWidth, initHeight), System.Drawing.GraphicsUnit.Pixel);

               //关键质量控制

               //获取系统编码类型数组,包含了jpeg,bmp,png,gif,tiff

               ImageCodecInfo[] icis = ImageCodecInfo.GetImageEncoders();

               ImageCodecInfo ici = null;

               foreach (ImageCodecInfo iin icis)

               {

                   if (i.MimeType =="image/jpeg" || i.MimeType == "image/bmp" || i.MimeType == "image/png" || i.MimeType == "image/gif")

                   {

                       ici = i;

                   }

               }

               EncoderParameters ep = newEncoderParameters(1);

               ep.Param[0] = newEncoderParameter(System.Drawing.Imaging.Encoder.Quality, (long)quality);

               //保存缩略图

               resultImage.Save(fileSaveUrl, ici, ep);

               //释放关键质量控制所用资源

               ep.Dispose();

               //释放缩略图资源

               resultG.Dispose();

               resultImage.Dispose();

               //释放原始图片资源

               initImage.Dispose();

           }

        }

        /// <summary>

        /// 正方型裁剪

        /// 以图片中心为轴心，截取正方型，然后等比缩放

        /// 用于头像处理

        /// </summary>

        /// <remarks>吴剑 2010-11-23</remarks>

        /// <param name="postedFile">原图HttpPostedFile对象</param>

        /// <param name="fileSaveUrl">缩略图存放地址</param>

        /// <param name="side">指定的边长（正方型）</param>

        /// <param name="quality">质量（范围0-100）</param>

        public staticvoid CutForSquare(System.IO.Stream fromFile,string fileSaveUrl,int side, int quality)

        {

           //创建目录

           string dir = Path.GetDirectoryName(fileSaveUrl);

           if (!Directory.Exists(dir))

               Directory.CreateDirectory(dir);

           //原始图片（获取原始图片创建对象，并使用流中嵌入的颜色管理信息）

           System.Drawing.Image initImage = System.Drawing.Image.FromStream(fromFile,true);

           //原图宽高均小于模版，不作处理，直接保存

           if (initImage.Width <= side && initImage.Height <= side)

           {

               initImage.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);

           }

           else

           {

               //原始图片的宽、高

               int initWidth = initImage.Width;

               int initHeight = initImage.Height;

               //非正方型先裁剪为正方型

               if (initWidth != initHeight)

               {

                   //截图对象

                   System.Drawing.Image pickedImage = null;

                   System.Drawing.Graphics pickedG = null;

                   //宽大于高的横图

                   if (initWidth > initHeight)

                   {

                       //对象实例化

                       pickedImage = newSystem.Drawing.Bitmap(initHeight, initHeight);

                       pickedG = System.Drawing.Graphics.FromImage(pickedImage);

                       //设置质量

                       pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

                       pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                       //定位

                       Rectangle fromR = newRectangle((initWidth - initHeight) / 2, 0, initHeight, initHeight);

                       Rectangle toR = newRectangle(0, 0, initHeight, initHeight);

                       //画图

                       pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);

                       //重置宽

                       initWidth = initHeight;

                   }

                   //高大于宽的竖图

                   else

                   {

                       //对象实例化

                       pickedImage = newSystem.Drawing.Bitmap(initWidth, initWidth);

                       pickedG = System.Drawing.Graphics.FromImage(pickedImage);

                       //设置质量

                       pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

                       pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                       //定位

                       Rectangle fromR = newRectangle(0, (initHeight - initWidth) / 2, initWidth, initWidth);

                       Rectangle toR = newRectangle(0, 0, initWidth, initWidth);

                       //画图

                       pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);

                       //重置高

                       initHeight = initWidth;

                   }

                   //将截图对象赋给原图

                   initImage = (System.Drawing.Image)pickedImage.Clone();

                   //释放截图资源

                   pickedG.Dispose();

                   pickedImage.Dispose();

               }

               //缩略图对象

               System.Drawing.Image resultImage = newSystem.Drawing.Bitmap(side, side);

               System.Drawing.Graphics resultG = System.Drawing.Graphics.FromImage(resultImage);

               //设置质量

               resultG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

               resultG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

               //用指定背景色清空画布

               resultG.Clear(Color.White);

               //绘制缩略图

               resultG.DrawImage(initImage, newSystem.Drawing.Rectangle(0, 0, side, side), newSystem.Drawing.Rectangle(0, 0, initWidth, initHeight), System.Drawing.GraphicsUnit.Pixel);

               //关键质量控制

               //获取系统编码类型数组,包含了jpeg,bmp,png,gif,tiff

               ImageCodecInfo[] icis = ImageCodecInfo.GetImageEncoders();

               ImageCodecInfo ici = null;

               foreach (ImageCodecInfo iin icis)

               {

                   if (i.MimeType =="image/jpeg" || i.MimeType == "image/bmp" || i.MimeType == "image/png" || i.MimeType == "image/gif")

                   {

                       ici = i;

                   }

               }

               EncoderParameters ep = newEncoderParameters(1);

               ep.Param[0] = newEncoderParameter(System.Drawing.Imaging.Encoder.Quality, (long)quality);

               //保存缩略图

               resultImage.Save(fileSaveUrl, ici, ep);

               //释放关键质量控制所用资源

               ep.Dispose();

               //释放缩略图资源

               resultG.Dispose();

               resultImage.Dispose();

               //释放原始图片资源

               initImage.Dispose();

           }

        }

        #endregion

        #region 固定模版裁剪并缩放

        /// <summary>

        /// 指定长宽裁剪

        /// 按模版比例最大范围的裁剪图片并缩放至模版尺寸

        /// </summary>

        /// <remarks>吴剑 2010-11-15</remarks>

        /// <param name="postedFile">原图HttpPostedFile对象</param>

        /// <param name="fileSaveUrl">保存路径</param>

        /// <param name="maxWidth">最大宽(单位:px)</param>

        /// <param name="maxHeight">最大高(单位:px)</param>

        /// <param name="quality">质量（范围0-100）</param>

        public staticvoid CutForCustom(System.Web.HttpPostedFile postedFile,string fileSaveUrl,int maxWidth,int maxHeight,int quality)

        {

           //从文件获取原始图片，并使用流中嵌入的颜色管理信息

           System.Drawing.Image initImage = System.Drawing.Image.FromStream(postedFile.InputStream,true);

           //原图宽高均小于模版，不作处理，直接保存

           if (initImage.Width <= maxWidth && initImage.Height <= maxHeight)

           {

               initImage.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);

           }

           else

           {

               //模版的宽高比例

               double templateRate = (double)maxWidth / maxHeight;

               //原图片的宽高比例

               double initRate = (double)initImage.Width / initImage.Height;

               //原图与模版比例相等，直接缩放

               if (templateRate == initRate)

               {

                   //按模版大小生成最终图片

                   System.Drawing.Image templateImage = newSystem.Drawing.Bitmap(maxWidth, maxHeight);

                   System.Drawing.Graphics templateG = System.Drawing.Graphics.FromImage(templateImage);

                   templateG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

                   templateG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                   templateG.Clear(Color.White);

                   templateG.DrawImage(initImage, newSystem.Drawing.Rectangle(0, 0, maxWidth, maxHeight), new System.Drawing.Rectangle(0, 0, initImage.Width, initImage.Height), System.Drawing.GraphicsUnit.Pixel);

                   templateImage.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);

               }

               //原图与模版比例不等，裁剪后缩放

               else

               {

                   //裁剪对象

                   System.Drawing.Image pickedImage = null;

                   System.Drawing.Graphics pickedG = null;

                   //定位

                   Rectangle fromR = newRectangle(0, 0, 0, 0);//原图裁剪定位

                   Rectangle toR = newRectangle(0, 0, 0, 0);//目标定位

                   //宽为标准进行裁剪

                   if (templateRate > initRate)

                   {

                       //裁剪对象实例化

                       pickedImage = newSystem.Drawing.Bitmap(initImage.Width, (int)Math.Floor(initImage.Width / templateRate));

                       pickedG = System.Drawing.Graphics.FromImage(pickedImage);

                       //裁剪源定位

                       fromR.X = 0;

                       fromR.Y = (int)Math.Floor((initImage.Height - initImage.Width / templateRate) / 2);

                       fromR.Width = initImage.Width;

                       fromR.Height = (int)Math.Floor(initImage.Width / templateRate);

                       //裁剪目标定位

                       toR.X = 0;

                       toR.Y = 0;

                       toR.Width = initImage.Width;

                       toR.Height = (int)Math.Floor(initImage.Width / templateRate);

                   }

                   //高为标准进行裁剪

                   else

                   {

                       pickedImage = newSystem.Drawing.Bitmap((int)Math.Floor(initImage.Height * templateRate), initImage.Height);

                       pickedG = System.Drawing.Graphics.FromImage(pickedImage);

                       fromR.X = (int)Math.Floor((initImage.Width - initImage.Height * templateRate) / 2);

                       fromR.Y = 0;

                       fromR.Width = (int)Math.Floor(initImage.Height * templateRate);

                       fromR.Height = initImage.Height;

                       toR.X = 0;

                       toR.Y = 0;

                       toR.Width = (int)Math.Floor(initImage.Height * templateRate);

                       toR.Height = initImage.Height;

                   }

                   //设置质量

                   pickedG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

                   pickedG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                   //裁剪

                   pickedG.DrawImage(initImage, toR, fromR, System.Drawing.GraphicsUnit.Pixel);

                   //按模版大小生成最终图片

                   System.Drawing.Image templateImage = newSystem.Drawing.Bitmap(maxWidth, maxHeight);

                   System.Drawing.Graphics templateG = System.Drawing.Graphics.FromImage(templateImage);

                   templateG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

                   templateG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

                   templateG.Clear(Color.White);

                   templateG.DrawImage(pickedImage, newSystem.Drawing.Rectangle(0, 0, maxWidth, maxHeight), new System.Drawing.Rectangle(0, 0, pickedImage.Width, pickedImage.Height), System.Drawing.GraphicsUnit.Pixel);

                   //关键质量控制

                   //获取系统编码类型数组,包含了jpeg,bmp,png,gif,tiff

                   ImageCodecInfo[] icis = ImageCodecInfo.GetImageEncoders();

                   ImageCodecInfo ici = null;

                   foreach (ImageCodecInfo iin icis)

                   {

                       if (i.MimeType =="image/jpeg" || i.MimeType == "image/bmp" || i.MimeType == "image/png" || i.MimeType == "image/gif")

                       {

                           ici = i;

                       }

                   }

                   EncoderParameters ep = newEncoderParameters(1);

                   ep.Param[0] = newEncoderParameter(System.Drawing.Imaging.Encoder.Quality, (long)quality);

                   //保存缩略图

                   templateImage.Save(fileSaveUrl, ici, ep);

                   //templateImage.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);

                   //释放资源

                   templateG.Dispose();

                   templateImage.Dispose();

                   pickedG.Dispose();

                   pickedImage.Dispose();

               }

           }

           //释放资源

           initImage.Dispose();

        }

        #endregion

        #region 等比缩放

        /// <summary>

        /// 图片等比缩放

        /// </summary>

        /// <remarks>吴剑 2011-01-21</remarks>

        /// <param name="postedFile">原图HttpPostedFile对象</param>

        /// <param name="savePath">缩略图存放地址</param>

        /// <param name="targetWidth">指定的最大宽度</param>

        /// <param name="targetHeight">指定的最大高度</param>

        /// <param name="watermarkText">水印文字(为""表示不使用水印)</param>

        /// <param name="watermarkImage">水印图片路径(为""表示不使用水印)</param>

        public staticvoid ZoomAuto(System.Web.HttpPostedFile postedFile,string savePath, System.Double targetWidth, System.Double targetHeight,string watermarkText,string watermarkImage)

        {

           //创建目录

           string dir = Path.GetDirectoryName(savePath);

           if (!Directory.Exists(dir))

               Directory.CreateDirectory(dir);

           //原始图片（获取原始图片创建对象，并使用流中嵌入的颜色管理信息）

           System.Drawing.Image initImage = System.Drawing.Image.FromStream(postedFile.InputStream,true);

           //原图宽高均小于模版，不作处理，直接保存

           if (initImage.Width <= targetWidth && initImage.Height <= targetHeight)

           {

               //文字水印

               if (watermarkText !="")

               {

                   using (System.Drawing.Graphics gWater = System.Drawing.Graphics.FromImage(initImage))

                   {

                       System.Drawing.Font fontWater = newFont("黑体", 10);

                       System.Drawing.Brush brushWater = newSolidBrush(Color.White);

                       gWater.DrawString(watermarkText, fontWater, brushWater, 10, 10);

                       gWater.Dispose();

                   }

               }

               //透明图片水印

               if (watermarkImage !="")

               {

                   if (File.Exists(watermarkImage))

                   {

                       //获取水印图片

                       using (System.Drawing.Image wrImage = System.Drawing.Image.FromFile(watermarkImage))

                       {

                           //水印绘制条件：原始图片宽高均大于或等于水印图片

                           if (initImage.Width >= wrImage.Width && initImage.Height >= wrImage.Height)

                           {

                               Graphics gWater = Graphics.FromImage(initImage);

                               //透明属性

                               ImageAttributes imgAttributes = newImageAttributes();

                               ColorMap colorMap = newColorMap();

                               colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);

                               colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);

                               ColorMap[] remapTable = { colorMap };

                               imgAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);

                               float[][] colorMatrixElements = {

                                  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,  0.5f, 0.0f},//透明度:0.5

                                  new float[] {0.0f,  0.0f,  0.0f,  0.0f, 1.0f}

                               };

                               ColorMatrix wmColorMatrix = newColorMatrix(colorMatrixElements);

                               imgAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);

                               gWater.DrawImage(wrImage, newRectangle(initImage.Width - wrImage.Width, initImage.Height - wrImage.Height, wrImage.Width, wrImage.Height), 0, 0, wrImage.Width, wrImage.Height, GraphicsUnit.Pixel, imgAttributes);

                               gWater.Dispose();

                           }

                           wrImage.Dispose();

                       }

                   }

               }

               //保存

               initImage.Save(savePath, System.Drawing.Imaging.ImageFormat.Jpeg);

           }

           else

           {

               //缩略图宽、高计算

               double newWidth = initImage.Width;

               double newHeight = initImage.Height;

               //宽大于高或宽等于高（横图或正方）

               if (initImage.Width > initImage.Height || initImage.Width == initImage.Height)

               {

                   //如果宽大于模版

                   if (initImage.Width > targetWidth)

                   {

                       //宽按模版，高按比例缩放

                       newWidth = targetWidth;

                       newHeight = initImage.Height * (targetWidth / initImage.Width);

                   }

               }

               //高大于宽（竖图）

               else

               {

                   //如果高大于模版

                   if (initImage.Height > targetHeight)

                   {

                       //高按模版，宽按比例缩放

                       newHeight = targetHeight;

                       newWidth = initImage.Width * (targetHeight / initImage.Height);

                   }

               }

               //生成新图

               //新建一个bmp图片

               System.Drawing.Image newImage = newSystem.Drawing.Bitmap((int)newWidth, (int)newHeight);

               //新建一个画板

               System.Drawing.Graphics newG = System.Drawing.Graphics.FromImage(newImage);

               //设置质量

               newG.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

               newG.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

               //置背景色

               newG.Clear(Color.White);

               //画图

               newG.DrawImage(initImage, newSystem.Drawing.Rectangle(0, 0, newImage.Width, newImage.Height),new System.Drawing.Rectangle(0, 0, initImage.Width, initImage.Height), System.Drawing.GraphicsUnit.Pixel);

               //文字水印

               if (watermarkText !="")

               {

                   using (System.Drawing.Graphics gWater = System.Drawing.Graphics.FromImage(newImage))

                   {

                       System.Drawing.Font fontWater = newFont("宋体", 10);

                       System.Drawing.Brush brushWater = newSolidBrush(Color.White);

                       gWater.DrawString(watermarkText, fontWater, brushWater, 10, 10);

                       gWater.Dispose();

                   }

               }

               //透明图片水印

               if (watermarkImage !="")

               {

                   if (File.Exists(watermarkImage))

                   {

                       //获取水印图片

                       using (System.Drawing.Image wrImage = System.Drawing.Image.FromFile(watermarkImage))

                       {

                           //水印绘制条件：原始图片宽高均大于或等于水印图片

                           if (newImage.Width >= wrImage.Width && newImage.Height >= wrImage.Height)

                           {

                               Graphics gWater = Graphics.FromImage(newImage);

                               //透明属性

                               ImageAttributes imgAttributes = newImageAttributes();

                               ColorMap colorMap = newColorMap();

                               colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);

                               colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);

                               ColorMap[] remapTable = { colorMap };

                               imgAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);

                               float[][] colorMatrixElements = {

                                  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,  0.5f, 0.0f},//透明度:0.5

                                  new float[] {0.0f,  0.0f,  0.0f,  0.0f, 1.0f}

                               };

                               ColorMatrix wmColorMatrix = newColorMatrix(colorMatrixElements);

                               imgAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default, ColorAdjustType.Bitmap);

                               gWater.DrawImage(wrImage, newRectangle(newImage.Width - wrImage.Width, newImage.Height - wrImage.Height, wrImage.Width, wrImage.Height), 0, 0, wrImage.Width, wrImage.Height, GraphicsUnit.Pixel, imgAttributes);

                               gWater.Dispose();

                           }

                           wrImage.Dispose();

                       }

                   }

               }

               //保存缩略图

               newImage.Save(savePath, System.Drawing.Imaging.ImageFormat.Jpeg);

               //释放资源

               newG.Dispose();

               newImage.Dispose();

               initImage.Dispose();

           }

        }

       

        #endregion       

        #region 其它

        /// <summary>

        /// 判断文件类型是否为WEB格式图片

        /// (注：JPG,GIF,BMP,PNG)

        /// </summary>

        /// <param name="contentType">HttpPostedFile.ContentType</param>

        /// <returns></returns>

        public staticbool IsWebImage(stringcontentType)

        {

           if (contentType =="image/pjpeg" || contentType == "image/jpeg" || contentType == "image/gif" || contentType == "image/bmp" || contentType == "image/png")

           {

               return true;

           }

           else

           {

               return false;

           }

        }

        #endregion

    }//end class

}