C#做图片查看器 如何实现图片的缩放

以下代码放在Click事件里即可
Bitmap bmp1=new BitMap(pictureBox1.Image);
Bitmap bmp2=new BitMap(pictureBox1.Image);
Graphics gre=pictureBox2.CrateGraphics();
gre.clear(pictureBox2.BackColor);
flost f=0.5f;
gre.ScaleTransfor(s,s);
gre.DrawImage(btmp1,this.pictureBox2.ClientRectangle,0,0,bmp2.Width,bmp2.Height,GraphicsUnit.Pixel);