/// <summary>叠加绘制图标</summary>
public static Image DrawIcon(this Image img, string iconUrl)
{
if (iconUrl.IsNotEmpty())
{
var icon = HttpHelper.GetNetworkImage(iconUrl);
int s = img.Width / 5;
icon = Painter.Thumbnail(icon, s, s);
var point = new Point((img.Width - s) / 2, (img.Height - s) / 2);
img = Painter.Merge(img, (Bitmap)icon, 0.95f, point);
icon.Dispose();
}
return(img);
}