生成缩略图+水印的方法

     //调用示例
     this.MakeSmallImg(f.PostedFile,this.Server.MapPath("1.jpg"),600,500);
     //------------------------------------------------------------
 
     public void MakeSmallImg(System.Web.HttpPostedFile postFile,string saveImg,System.Double Width,System.Double Height)
{
 
     //原始图片名称
     string originalFilename = postFile.FileName;
     //生成的高质量图片名称
     string strGoodFile = saveImg;
 
 
     //从文件取得图片对象
     System.Drawing.Image image = System.Drawing.Image.FromStream(postFile.InputStream,true);
 
     System.Double NewWidth,NewHeight;
     if(image.Width>image.Height)
{
     NewWidth=Width;
     NewHeight=image.Height*(NewWidth/image.Width);
}
     else
{
     NewHeight=Height;
     NewWidth=(NewHeight/image.Height)*image.Width;
}
 
     if (NewWidth>Width)
{
     NewWidth=Width;
}
     if (NewHeight>Height)
{
     NewHeight=Height;
}
 
     //取得图片大小
     System.Drawing.Size size = new Size((int)NewWidth,(int)NewHeight);
     //新建一个bmp图片
     System.Drawing.Image bitmap = new System.Drawing.Bitmap(size.Width,size.Height);
     //新建一个画板
     System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap);
     //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;
     //清空一下画布
     g.Clear(Color.White);
     //在指定位置画图
     g.DrawImage(image, new System.Drawing.Rectangle(0, 0, bitmap.Width, bitmap.Height),
     new System.Drawing.Rectangle(0, 0, image.Width,image.Height),
     System.Drawing.GraphicsUnit.Pixel);
 
 
     ///文字水印
     //System.Drawing.Graphics G=System.Drawing.Graphics.FromImage(bitmap);
     //System.Drawing.Font f=new Font("宋体",10);
     //System.Drawing.Brush b=new SolidBrush(Color.Black);
     //G.DrawString("myohmine",f,b,10,10);
     //G.Dispose();
 
 
 
     ///图片水印
     //System.Drawing.Image copyImage = System.Drawing.Image.FromFile(System.Web.HttpContext.Current.Server.MapPath("pic/1.gif"));
     //Graphics a = Graphics.FromImage(bitmap);
     //a.DrawImage(copyImage, new Rectangle(bitmap.Width-copyImage.Width,bitmap.Height-copyImage.Height,copyImage.Width, copyImage.Height),0,0, copyImage.Width, copyImage.Height, GraphicsUnit.Pixel);
 
     //copyImage.Dispose();
     //a.Dispose();
     //copyImage.Dispose();
 
 
     //保存高清晰度的缩略图
     bitmap.Save(strGoodFile, System.Drawing.Imaging.ImageFormat.Jpeg);
 
     g.Dispose();
     image.Dispose();
     bitmap.Dispose();
}
 
posted @ 2006-04-07 15:43  ZetaChow晓代码  阅读(199)  评论(0编辑  收藏  举报