Net上传图片按比例自动缩小或放大

以下为引用的内容：

//// <summary>         /// 按比例缩小图片，自动计算宽度     /// </summary>         /// <param name="strOldPic">源图文件名(包括路径)</param>         /// <param name="strNewPic">缩小后保存为文件名(包括路径)</param>         /// <param name="intHeight">缩小至高度</param>         public void SmallPicWidth(string strOldPic, string strNewPic, int intHeight)         {             System.Drawing.Bitmap objPic, objNewPic;             try             {                 objPic = new System.Drawing.Bitmap(strOldPic);                 int intWidth = (intHeight / objPic.Height) * objPic.Width;                 objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);                 objNewPic.Save(strNewPic);             }             catch (Exception exp) { throw exp; }             finally             {                 objPic = null;                 objNewPic = null;             }         }         /**//// <summary>         /// 缩小图片     /// </summary>         /// <param name="strOldPic">源图文件名(包括路径)</param>         /// <param name="strNewPic">缩小后保存为文件名(包括路径)</param>         /// <param name="intWidth">缩小至宽度</param>         /// <param name="intHeight">缩小至高度</param>         public void SmallPic(string strOldPic, string strNewPic, int intWidth, int intHeight)         {             System.Drawing.Bitmap objPic, objNewPic;             try             {                 objPic = new System.Drawing.Bitmap(strOldPic);                 objNewPic = new System.Drawing.Bitmap(objPic, intWidth, intHeight);                 objNewPic.Save(strNewPic);             }             catch (Exception exp)                 { throw exp; }             finally             {                 objPic = null;                 objNewPic = null;             }         }

 

 

来自 http://www.cnblogs.com/luluping/archive/2009/03/05/1403571.html