.NET用QrCodeNet来生成二维码

需要引用ThoughtWorks.QRCode.dll

需要引用命名空间为

using Gma.QrCodeNet.Encoding;using Gma.QrCodeNet.Encoding.Windows.Render;

using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using Gma.QrCodeNet.Encoding;
using Gma.QrCodeNet.Encoding.Windows.Render;

namespace QRCodeDemo
{
    public class QRCodeHelper
    {
        /// 
  
        /// 生成二维码  
        /// 
  
        /// 内容
        /// 二维码的大小
        /// 输出流  
        public static MemoryStream GetQRCode(string content, int moduleSize = 9)
        {
            //ErrorCorrectionLevel 误差校正水平
            //QuietZoneModules     空白区域

            var encoder = new QrEncoder(ErrorCorrectionLevel.M);
            QrCode qrCode = encoder.Encode(content);
            GraphicsRenderer render = new GraphicsRenderer(new FixedModuleSize(moduleSize, QuietZoneModules.Two) , Brushes.Black, Brushes.White);

            MemoryStream memoryStream = new MemoryStream();
            render.WriteToStream(qrCode.Matrix, ImageFormat.Jpeg, memoryStream);
            
            return memoryStream;

            //生成图片的代码
            //DrawingSize dSize = render.SizeCalculator.GetSize(qrCode.Matrix.Width);
            //Bitmap map = new Bitmap(dSize.CodeWidth, dSize.CodeWidth);
            //Graphics g = Graphics.FromImage(map);
            //render.Draw(g, qrCode.Matrix);
            //map.Save(fileName, ImageFormat.Jpeg);//fileName为存放的图片路径
        }

        /// 

        /// 生成带Logo二维码  
        /// 
        /// 内容
        /// logo路径
        /// 二维码的大小
        /// 输出流
        public static MemoryStream GetQRCode(string content, string iconPath, int moduleSize = 9)
        {
            QrEncoder qrEncoder = new QrEncoder(ErrorCorrectionLevel.M);
            QrCode qrCode = qrEncoder.Encode(content);
            
            GraphicsRenderer render = new GraphicsRenderer(new FixedModuleSize(moduleSize, QuietZoneModules.Two), Brushes.Black, Brushes.White);

            DrawingSize dSize = render.SizeCalculator.GetSize(qrCode.Matrix.Width);
            Bitmap map = new Bitmap(dSize.CodeWidth, dSize.CodeWidth);
            Graphics g = Graphics.FromImage(map);
            render.Draw(g, qrCode.Matrix);

            //追加Logo图片 ,注意控制Logo图片大小和二维码大小的比例
            //PS:追加的图片过大超过二维码的容错率会导致信息丢失,无法被识别
            Image img = Image.FromFile(iconPath);

            Point imgPoint = new Point((map.Width - img.Width) / 2, (map.Height - img.Height) / 2);
            g.DrawImage(img, imgPoint.X, imgPoint.Y, img.Width, img.Height);

            MemoryStream memoryStream = new MemoryStream();
            map.Save(memoryStream, ImageFormat.Jpeg);

            return memoryStream;

            //生成图片的代码： map.Save(fileName, ImageFormat.Jpeg);//fileName为存放的图片路径
        }
    }
}