private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
int x = e.X;
int y = e.Y;
using (Bitmap bmp = new Bitmap(AppDomain.CurrentDomain.BaseDirectory + "werty.png"))
{
Color pixelColor = bmp.GetPixel(x, y);

//像素点颜色的 Alpha 值
byte alpha = pixelColor.A;
//颜色的 RED 分量值
byte red = pixelColor.R;
//颜色的 GREEN 分量值
byte green = pixelColor.G;
//颜色的 BLUE 分量值
byte blue = pixelColor.B;

}

}