picturebox 加载了一个图片后，如何在上面画线，如何合并图和画线的结果
如题

[解决办法]
private void button1_Click(object sender, EventArgs e)
{
Graphics vGraphics = Graphics.FromImage(pictureBox1.Image);
vGraphics.DrawLine(Pens.Blue, new Point(0, 0), new Point(100, 16));
pictureBox1.Invalidate();

pictureBox1.Image.Save(@ "c:\temp\temp.bmp ");
}

[解决办法]
一楼正解。。接分