Dim SngPer As Single = 1 / 2 '放大或缩小的比例 放大2倍时SngPer=2,缩小3倍时 SngPer=1/3

        Dim PicOld As Image = Image.FromFile("d:\原始图片.JPG")

        Dim PicNew As New System.Drawing.Bitmap(PicOld, PicOld.Width * SngPer, PicOld.Height * SngPer)

        PictureBox1.Image = PicNew