二维码生成方法

    #region 二维码生成基础方法
        /// <summary>
        /// 生成用户信息的二维码
        /// </summary>
        /// <param name="url">要生成的字符串</param>
        /// <param name="headPhoto">要贴到二维码上面的头像</param>
        /// <param name="filePath">文件的保存路径</param>
        /// <returns></returns>
        public string SaveCodeImg(string url, string headPhoto, string filePath)
        {
            var fileName = GetFileNameByDate();
            var path = Path.Combine(filePath, fileName);
            QrEncoder qrEncoder = new QrEncoder(ErrorCorrectionLevel.H);
            QrCode qrCode = new QrCode();
            qrEncoder.TryEncode(url, out qrCode);
            var renderer = new GraphicsRenderer(new FixedModuleSize(4, QuietZoneModules.Two));
            //var image = new Bitmap();
            Image img = new Bitmap(200, 200);
            Image qrcode = new Bitmap(200, 200);
            using (Graphics g = Graphics.FromImage(img))
            {
                renderer.Draw(g, qrCode.Matrix);
                g.DrawImage(img, new Point { X = 0, Y = 0 });
                //using (MemoryStream stream = new MemoryStream())
                //{
                //    img.Save(stream, ImageFormat.Jpeg);
                //}
                if (string.IsNullOrEmpty(headPhoto) || !File.Exists(headPhoto))
                {
                   // img.Save(path+".jpg");
                    qrcode = img;
                    qrcode.Save(path+".jpg");
                }
                else
                {
                    qrcode = CombinImage(img, headPhoto);
                    qrcode.Save(path + ".jpg");
                }
            }
            return fileName+".jpg";
        }
        private string GetFileNameByDate()
        {
            string productnumber = "";
            //按年月日生成前12位
            productnumber = DateTime.Now.Year.ToString().Substring(2, 2) + DateTime.Now.Month.ToString().PadLeft(2, ‘0‘) + DateTime.Now.Day.ToString().PadLeft(2, ‘0‘);
            productnumber += DateTime.Now.Hour.ToString().PadLeft(2, ‘0‘);
            // +DateTime.Now.Minute.ToString().PadLeft(2, ‘0‘) + DateTime.Now.Second.ToString().PadLeft(2, ‘0‘);
            //随即数生成4位
            var rnd = new Random((int)DateTime.Now.Ticks);
            productnumber += rnd.Next(0, 9999).ToString().PadLeft(4, ‘0‘);
            return productnumber;
        }
        public static Image CombinImage(Image imgBack, string destImg)
        {
            Image img = Image.FromFile(destImg);        //照片图片    
            if (img.Height != 65 || img.Width != 65)
            {
                img = KiResizeImage(img, 65, 65, 0);
            }
            Graphics g = Graphics.FromImage(imgBack);

            g.DrawImage(imgBack, 0, 0, imgBack.Width, imgBack.Height);      //g.DrawImage(imgBack, 0, 0, 相框宽, 相框高);   

            //g.FillRectangle(System.Drawing.Brushes.White, imgBack.Width / 2 - img.Width / 2 - 1, imgBack.Width / 2 - img.Width / 2 - 1,1,1);//相片四周刷一层黑色边框  

            //g.DrawImage(img, 照片与相框的左边距, 照片与相框的上边距, 照片宽, 照片高);  

            g.DrawImage(img, imgBack.Width / 2 - img.Width / 2, imgBack.Width / 2 - img.Width / 2, img.Width, img.Height);
            GC.Collect();
            return imgBack;
        }
        public static Image KiResizeImage(Image bmp, int newW, int newH, int Mode)
        {
            try
            {
                Image b = new Bitmap(newW, newH);
                Graphics g = Graphics.FromImage(b);
                // 插值算法的质量  
                g.InterpolationMode = InterpolationMode.HighQualityBicubic;
                g.DrawImage(bmp, new Rectangle(0, 0, newW, newH), new Rectangle(0, 0, bmp.Width, bmp.Height), GraphicsUnit.Pixel);
                g.Dispose();
                return b;
            }
            catch
            {
                return null;
            }
        }

        #endregion