C#实现二维码和条形码生成与打印

一、技术选型与依赖库

核心库选择

• ZXing.Net：开源条码处理库，支持QR Code、Code 128等格式

  Install-Package ZXing.Net
  

• QRCoder：纯C#实现的二维码生成库

  Install-Package QRCoder
  

---

二、代码实现

2.1 二维码生成（ZXing.Net）

using ZXing;
using ZXing.Common;

public class QRCodeGenerator
{
    public Bitmap GenerateQRCode(string content, int size = 300)
    {
        var writer = new BarcodeWriter
        {
            Format = BarcodeFormat.QR_CODE,
            Options = new EncodingOptions
            {
                Width = size,
                Height = size,
                Margin = 1,
                PureBarcode = true
            }
        };
        
        // 添加纠错级别（L/M/Q/H）
        writer.Options.Hints.Add(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        
        return writer.Write(content);
    }
}

2.2 条形码生成（Code 128）

public class BarcodeGenerator
{
    public Bitmap GenerateCode128(string data)
    {
        var options = new EncodingOptions
        {
            Height = 100,
            Width = 400,
            Margin = 2
        };
        
        using (var writer = new BarcodeWriter
        {
            Format = BarcodeFormat.CODE_128,
            Options = options
        })
        {
            return writer.Write(data);
        }
    }
}

---

三、图像处理与优化

3.1 图像增强

public Bitmap EnhanceImage(Bitmap source)
{
    using (var graphics = Graphics.FromImage(source))
    {
        graphics.SmoothingMode = SmoothingMode.AntiAlias;
        graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
        graphics.PixelOffsetMode = PixelOffsetMode.HighQualityBilinear;
        
        // 添加边框
        var border = new Pen(Color.Black, 2);
        graphics.DrawRectangle(border, 0, 0, source.Width-1, source.Height-1);
        
        return source;
    }
}

3.2 图像保存

public void SaveImage(Bitmap image, string path)
{
    ImageCodecInfo jpegEncoder = GetEncoder(ImageFormat.Jpeg);
    EncoderParameters encoderParams = new EncoderParameters(1);
    encoderParams.Param[0] = new EncoderParameter(Encoder.Quality, 90L);
    
    image.Save(path, jpegEncoder, encoderParams);
}

private ImageCodecInfo GetEncoder(ImageFormat format)
{
    ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
    foreach (var codec in codecs)
    {
        if (codec.FormatID == format.Guid)
            return codec;
    }
    return null;
}

---

四、打印实现方案

4.1 本地打印（Win32 API）

using System.Drawing.Printing;

public class PrinterService
{
    public void PrintBitmap(Bitmap image)
    {
        using (var printDoc = new PrintDocument())
        {
            printDoc.PrinterSettings.PrinterName = "Zebra ZT410"; // 指定打印机
            printDoc.DefaultPageSettings.PaperSize = new PaperSize("Custom", 400, 300);
            
            printDoc.PrintPage += (s, e) => 
            {
                e.Graphics.DrawImage(image, 0, 0, image.Width, image.Height);
            };
            
            printDoc.Print();
        }
    }
}

4.2 网络打印（TCP/IP）

public class NetworkPrinter
{
    public void SendToPrinter(string ip, Bitmap image)
    {
        using (var client = new TcpClient(ip, 9100))
        {
            using (var stream = client.GetStream())
            {
                var ms = new MemoryStream();
                image.Save(ms, ImageFormat.Png);
                stream.Write(ms.ToArray(), 0, ms.Length);
            }
        }
    }
}

---

五、高级功能实现

5.1 ZPL指令打印（斑马打印机）

public string GenerateZPL(string content)
{
    return $@"
    ^XA
    ^FO50,50
    ^BQN,2,8
    ^FD{content}^FS
    ^XZ";
}

// 发送指令
using (var client = new TcpClient("192.168.1.100", 9100))
{
    NetworkStream stream = client.GetStream();
    byte[] data = Encoding.ASCII.GetBytes(zplCommand);
    stream.Write(data, 0, data.Length);
}

5.2 批量打印管理

public class PrintQueue
{
    private Queue<PrintJob> _jobs = new Queue<PrintJob>();
    
    public void Enqueue(PrintJob job)
    {
        _jobs.Enqueue(job);
    }
    
    public async Task ProcessQueueAsync()
    {
        while (_jobs.Count > 0)
        {
            var job = _jobs.Dequeue();
            await PrintService.PrintAsync(job.Bitmap);
            await Task.Delay(1000); // 防卡纸间隔
        }
    }
}

参考代码 C#二维码和条形码生成 打印处理 www.youwenfan.com/contentcnh/57421.html

六、异常处理与日志

6.1 异常捕获

public void SafePrint(Action printAction)
{
    try
    {
        printAction();
    }
    catch (TimeoutException ex)
    {
        Logger.LogError($"打印超时: {ex.Message}");
        RestartPrinter();
    }
    catch (IOException ex)
    {
        Logger.LogError($"设备断开: {ex.Message}");
    }
}

6.2 日志记录

public static class Logger
{
    private static readonly string logPath = "print_log.txt";
    
    public static void LogError(string message)
    {
        File.AppendAllText(logPath, 
            $"{DateTime.Now:yyyy-MM-dd HH:mm:ss} [ERROR] {message}{Environment.NewLine}");
    }
}

---

七、性能优化

1. 图像缓存

   private static Dictionary<string, Bitmap> _imageCache = new Dictionary<string, Bitmap>();
   
   public Bitmap GetCachedImage(string key, Func<Bitmap> generateFunc)
   {
       if (!_imageCache.ContainsKey(key))
       {
           _imageCache[key] = generateFunc();
       }
       return _imageCache[key];
   }
   

2. 异步处理

   public async Task<Bitmap> GenerateAsync(string data)
   {
       return await Task.Run(() => GenerateQRCode(data));
   }
   

3. 批量生成优化

   public void BatchGenerate(List<string> dataList)
   {
       Parallel.ForEach(dataList, item => 
       {
           var img = GenerateQRCode(item);
           SaveImage(img, $"{Guid.NewGuid()}.png");
       });
   }
   

---

八、部署建议

1. 硬件要求

   • 最低配置：i5-8代/8GB内存
   • 推荐配置：i7-12代/16GB内存+NVIDIA显卡（GPU加速）

2. 环境配置

   <!-- app.config -->
   <configuration>
     <system.drawing>
       <PrinterSettings>
         <add key="DefaultPrinter" value="Zebra ZT410"/>
       </PrinterSettings>
     </system.drawing>
   </configuration>
   

3. 安全措施

   • 打印内容加密：AES加密敏感数据
   • 访问控制：IP白名单验证

   public bool ValidateIP(string ip)
   {
       return allowedIPs.Contains(ip);
   }
   

---

九、测试用例

[TestClass]
public class PrintTests
{
    [TestMethod]
    public void TestQRCodePrint()
    {
        var generator = new QRCodeGenerator();
        var bitmap = generator.GenerateQRCode("https://test.com");
        
        using (var ms = new MemoryStream())
        {
            bitmap.Save(ms, ImageFormat.Png);
            Assert.IsTrue(ms.Length > 1024); // 最小尺寸验证
        }
    }
}