QrEncoder qrEncoder = new QrEncoder(ErrorCorrectionLevel.H);
QrCode qrCode = new QrCode();
qrEncoder.TryEncode("http://www.xxx.com", out qrCode);
int ModuleSize = 6;
QuietZoneModules QuietZone = QuietZoneModules.Two;
var render = new GraphicsRenderer(new FixedModuleSize(ModuleSize, QuietZone));
using (Stream stream = File.OpenWrite("d:/1.png"))
{
    render.WriteToStream(qrCode.Matrix,ImageFormat.Png,stream);
}
Console.WriteLine("生成成功");
Console.ReadKey();