合并图片
Dim imgback As image = getimage("d:\a.png") '主图
Dim bmp As new bitmap(imgback.width, imgback.height)
Dim g As System.Drawing.Graphics = System.Drawing.Graphics.FromImage(bmp)
g.DrawImage(imgback, 0, 0, imgback.Width, imgback.Height) '绘制主图'
Dim img = GetImage("d:\b.png") '获取副图片
Dim x As Integer = imgback.Width - 120 '副图距离主图左边距
Dim y As Integer = imgback.height - 120 '副图距离主图上边距
g.DrawImage(img, x, y, 100, 100) '绘制第二张图片
bmp.Save("d:\c.jpg") '保存
bmp.dispose '释放资源'