.net实现裁剪网站上传图片的方法

using System;  using System.Collections.Generic;  using System.Text;  using System.Drawing;   public class Cut  {    /// <summary>    /// 裁剪图片    /// </summary>    /// <param name="sourceImg">原图片路径</param>    /// <param name="desImg">裁剪图片路径</param>    /// <param name="left">X</param>    /// <param name="top">Y</param>    /// <param name="width">宽</param>    /// <param name="height">高</param>    public static void CutImage(string sourceImg, string desImg, int left, int top, int width, int height)    {      System.Drawing.Image img = System.Drawing.Bitmap.FromFile(sourceImg);      System.Drawing.Image imgToSave = new System.Drawing.Bitmap(width, height);      System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(imgToSave);      RectangleF sourceRect = new RectangleF(left, top, width, height);      RectangleF destinationRect = new RectangleF(0, 0, width, height);       g.DrawImage(img,            destinationRect,            sourceRect,            GraphicsUnit.Pixel            );      g.Save();      imgToSave.Save(desImg, System.Drawing.Imaging.ImageFormat.Jpeg);      g.Dispose();      imgToSave.Dispose();      img.Dispose();    }    }  

using System;  using System.Web;  using System.Drawing;  using System.IO;   public class ImgCropper_WebHandler : IHttpHandler  {    public void ProcessRequest(HttpContext context)    {      string Pic = Convert.ToString(context.Request["p"]);      int PointX = Convert.ToInt32(context.Request["x"]);      int PointY = Convert.ToInt32(context.Request["y"]);      int CutWidth = Convert.ToInt32(context.Request["w"]);      int CutHeight = Convert.ToInt32(context.Request["h"]);      int PicWidth = Convert.ToInt32(context.Request["pw"]);      int PicHeight = Convert.ToInt32(context.Request["ph"]);       context.Response.ContentType = "image/jpeg";      ResetImg(context, System.Web.HttpContext.Current.Server.MapPath(Pic), PicWidth, PicHeight, PointX, PointY, CutWidth, CutHeight).WriteTo(context.Response.OutputStream);    }     public MemoryStream ResetImg(HttpContext context, string ImgFile, int PicWidth, int PicHeight, int PointX, int PointY, int CutWidth, int CutHeight)    {      Image imgPhoto = Image.FromFile(ImgFile);      Bitmap bmPhoto = new Bitmap(CutWidth, CutHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb);       Graphics gbmPhoto = Graphics.FromImage(bmPhoto);      gbmPhoto.DrawImage(imgPhoto, new Rectangle(0, 0, CutWidth, CutHeight), PointX * imgPhoto.Width / PicWidth, PointY * imgPhoto.Height / PicHeight, CutWidth * imgPhoto.Width / PicWidth, CutHeight * imgPhoto.Height / PicHeight, GraphicsUnit.Pixel);       //保存图片到服务器      bmPhoto.Save(context.Server.MapPath("upload/") + Guid.NewGuid() + ".jpg", System.Drawing.Imaging.ImageFormat.Jpeg);       //生成文件流回传      MemoryStream ms2 = new MemoryStream();      bmPhoto.Save(ms2, System.Drawing.Imaging.ImageFormat.Jpeg);       imgPhoto.Dispose();      gbmPhoto.Dispose();      bmPhoto.Dispose();       return ms2;    }      public bool IsReusable    {      get     {        return false;      }    }  }