asp.net ͼƬˮӡ

string mapho = request["imgpath"];//»ñȡij¸öÒ³Ãæ´«¹ýµÄͼƬÃû³Æ
  string str1 = Server.MapPath(mapho);//ÒªÌí¼ÓˮӡµÄͼƬ
  string str2 = Server.MapPath("WaterMark.jpg");//Ìí¼ÓµÄÄÚÈÝͼƬ
  System.Drawing.Image bmp = System.Drawing.Image.fromFile(str1);
  Graphics gs = Graphics.fromImage(bmp);
System.Drawing.Image bmp2 = System.Drawing.Image.fromFile(str2);
  //Á½ÕÅͼƬºÏ²¢
  gs.DrawImage(bmp2, bmp.Width-bmp2.Width, bmp.Height - bmp2.Height, bmp2.Width, bmp2.Height);
  Response.ContentType = "image/jpeg";//Êä³öÀàÐÍ
  bmp.Save(Response.OutputStream,ImageFormat.Jpeg);//±£´æ
Ó÷¨:
н¨Ò»¸öÒ³ÃæÔÚÒ³Ãæ¼ÓÔØʼþÀïÌí¼ÓÒÔÉÏ´úÂë¡£
ÔÚÒªÓÃÕâ¸öͼƬµÄʱºò°ÑËüµÄͼƬURLµØÖ·µÈÓÚÕâ¸öÒ³Ãæ¾Í¿ÉÒÔÁË.
ÀýÈ磺<asp:image runat="server" ImageUrl="ÒÔÉÏÒ³ÃæµÄÃû³Æ.aspx?imgpath="+"ͼƬÃû³Æ"></asp:image>