C#Qrcode生成二维码支持带标题

　　过程不在叙述，

1. 通过NuGet进行安装“ThoughtWorks.QRCode”
2. 生成二维码的方法

   /// <summary>
           /// 生成二维码
           /// </summary>
           /// <param name="enCodeString">二维码内容</param>
           /// <param name="filePath">路径</param>
           /// <param name="qrCodeScale">大小</param>
           /// <returns></returns>
           public static string QRCode(string enCodeString, string filePath = "", int qrCodeScale = 12)
           {
               System.Drawing.Bitmap bt;
   
               QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
               qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;//编码方式(注意：BYTE能支持中文，ALPHA_NUMERIC扫描出来的都是数字)
               qrCodeEncoder.QRCodeScale = qrCodeScale;//大小(值越大生成的二维码图片像素越高)
               qrCodeEncoder.QRCodeVersion = 0;//版本(注意：设置为0主要是防止编码的字符串太长时发生错误)
               qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;//错误效验、错误更正(有4个等级)
               qrCodeEncoder.QRCodeBackgroundColor = Color.Black;//背景色
               qrCodeEncoder.QRCodeForegroundColor = Color.White;//前景色
   
   
               bt = qrCodeEncoder.Encode(enCodeString, Encoding.UTF8);
   
               string filename = Guid.NewGuid().ToString();
               //string file_path = string.Empty; ;
               if (string.IsNullOrEmpty(filePath))
               {
                   filePath = AppDomain.CurrentDomain.BaseDirectory + "QRCode";
               }
               string codeUrl =$"{filePath}\{filename}.jpg";
   
               //根据文件名称，自动建立对应目录
               if (!System.IO.Directory.Exists(filePath))
                   System.IO.Directory.CreateDirectory(filePath);
               //bt=KiSetText(bt, "test", 10, 10);
               bt.Save(codeUrl);//保存图片
               return codeUrl;
           }
   

   　　

3. 如果需要增加标题，则添加方法

   public static Bitmap KiSetText(Bitmap b, string txt, int x, int y)
           {
               if (b == null)
               {
                   return null;
               }
   
               Bitmap resizeImage = new Bitmap(b.Width, b.Height + 40);
               Graphics gfx = Graphics.FromImage(resizeImage);
               gfx.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAlias;
   
               gfx.FillRectangle(Brushes.White, new Rectangle(0, 0, 400, 100));
   
               gfx.DrawImageUnscaled(b, 0, 40);
   
               // 作为演示，我们用Arial字体，大小为32，红色。
               FontFamily fm = new FontFamily("Arial");
               Font font = new Font(fm, 24, FontStyle.Regular, GraphicsUnit.Pixel);
               SolidBrush sb = new SolidBrush(Color.Black);
   
               gfx.DrawString(txt, font, sb, new PointF(x, y));
               gfx.Dispose();
   
               return resizeImage;
           }