C# 中使用 ThoughtWorks.QRCode.dll 生成指定尺寸和边框宽度的二维码

本文介绍在 C# 中使用 ThoughtWorks.QRCode.dll 生成指定尺寸和边框宽度的二维码。网上文章大多只是简单介绍内置参数的设置,根据我的使用目的,增加了自定义目标二维码图片尺寸和白边边框。有需要的朋友们可以试一下,如有bug欢迎指正。

 首先,将 ThoughtWorks.QRCode.dll 放在 bin 目录后,在页面中引用:

using ThoughtWorks.QRCode.Codec;
 
生成二维码图片:
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/// <summary>
/// 生成二维码
/// </summary>
/// <param name="Content">内容文本</param>
/// <param name="QRCodeEncodeMode">二维码编码方式</param>
/// <param name="QRCodeErrorCorrect">纠错码等级</param>
/// <param name="QRCodeVersion">二维码版本号 0-40</param>
/// <param name="QRCodeScale">每个小方格的预设宽度(像素),正整数</param>
/// <param name="size">图片尺寸(像素),0表示不设置</param>
/// <param name="border">图片白边(像素),当size大于0时有效</param>
/// <returns></returns>
public System.Drawing.Image CreateQRCode(string Content, QRCodeEncoder.ENCODE_MODE QRCodeEncodeMode, QRCodeEncoder.ERROR_CORRECTION QRCodeErrorCorrect, int QRCodeVersion, int QRCodeScale, int size, int border)
{
    QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
    qrCodeEncoder.QRCodeEncodeMode = QRCodeEncodeMode;
    qrCodeEncoder.QRCodeErrorCorrect = QRCodeErrorCorrect;
    qrCodeEncoder.QRCodeScale = QRCodeScale;
    qrCodeEncoder.QRCodeVersion = QRCodeVersion;
    System.Drawing.Image image = qrCodeEncoder.Encode(Content);
      
    #region 根据设定的目标图片尺寸调整二维码QRCodeScale设置,并添加边框
    if (size > 0)
    {
        //当设定目标图片尺寸大于生成的尺寸时,逐步增大方格尺寸
        #region 当设定目标图片尺寸大于生成的尺寸时,逐步增大方格尺寸
        while (image.Width < size)
        {
            qrCodeEncoder.QRCodeScale++;
            System.Drawing.Image imageNew = qrCodeEncoder.Encode(Content);
            if (imageNew.Width < size)
            {
                image = new System.Drawing.Bitmap(imageNew);
                imageNew.Dispose();
                imageNew = null;
            }
            else
            {
                qrCodeEncoder.QRCodeScale--; //新尺寸未采用,恢复最终使用的尺寸
                imageNew.Dispose();
                imageNew = null;
                break;
            }
        }
        #endregion
          
        //当设定目标图片尺寸小于生成的尺寸时,逐步减小方格尺寸
        #region 当设定目标图片尺寸小于生成的尺寸时,逐步减小方格尺寸
        while (image.Width > size && qrCodeEncoder.QRCodeScale > 1)
        {
            qrCodeEncoder.QRCodeScale--;
            System.Drawing.Image imageNew = qrCodeEncoder.Encode(Content);
            image = new System.Drawing.Bitmap(imageNew);
            imageNew.Dispose();
            imageNew = null;
            if (image.Width < size)
            {
                break;
            }
        }
        #endregion
          
        //如果目标尺寸大于生成的图片尺寸,则为图片增加白边
        #region 如果目标尺寸大于生成的图片尺寸,则为图片增加白边
        if (image.Width <= size)
        {
            //根据参数设置二维码图片白边的最小宽度
            #region 根据参数设置二维码图片白边的最小宽度
            if (border > 0)
            {
                while (image.Width <= size && size - image.Width < border * 2 && qrCodeEncoder.QRCodeScale > 1)
                {
                    qrCodeEncoder.QRCodeScale--;
                    System.Drawing.Image imageNew = qrCodeEncoder.Encode(Content);
                    image = new System.Drawing.Bitmap(imageNew);
                    imageNew.Dispose();
                    imageNew = null;
                }
            }
            #endregion
  
            //当目标图片尺寸大于二维码尺寸时,将二维码绘制在目标尺寸白色画布的中心位置
            if (image.Width < size)
            {
                //新建空白绘图
                System.Drawing.Bitmap panel = new System.Drawing.Bitmap(size, size);
                System.Drawing.Graphics graphic0 = System.Drawing.Graphics.FromImage(panel);
                int p_left = 0;
                int p_top = 0;
                if (image.Width <= size) //如果原图比目标形状宽
                {
                    p_left = (size - image.Width) / 2;
                }
                if (image.Height <= size)
                {
                    p_top = (size - image.Height) / 2;
                }
                  
                //将生成的二维码图像粘贴至绘图的中心位置
                graphic0.DrawImage(image, p_left, p_top, image.Width, image.Height);
                image = new System.Drawing.Bitmap(panel);
                panel.Dispose();
                panel = null;
                graphic0.Dispose();
                graphic0 = null;
            }
        }
        #endregion
    }
    #endregion
    return image;
}
  
private static bool IsTrue() // 在Image类别对图片进行缩放的时候,需要一个返回bool类别的委托
{
    return true;
}

 在aspx页面调用和输出为图片流:

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string content = string.IsNullOrEmpty(Request.QueryString["txt"]) ? "http://www.lenashane.com/" : Request.QueryString["txt"];
int size = Convert.ToInt32(string.IsNullOrEmpty(Request.QueryString["size"]) ? "200" : Request.QueryString["size"]);
int border = Convert.ToInt32(string.IsNullOrEmpty(Request.QueryString["border"]) ? "10" : Request.QueryString["border"]);
  
System.Drawing.Image image = CreateQRCode(content,
    QRCodeEncoder.ENCODE_MODE.BYTE,
    QRCodeEncoder.ERROR_CORRECTION.M,
    0,
    5,
    size,
    border);
  
//将图片输出到页面
System.IO.MemoryStream ms = new System.IO.MemoryStream();
image.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
HttpContext.Current.Response.ClearContent();
HttpContext.Current.Response.ContentType = "image/Png";
HttpContext.Current.Response.OutputStream.Write(ms.ToArray(), 0, ms.ToArray().Length);
HttpContext.Current.Response.End();
  
ms.Close();
ms = null;
image.Dispose();
image = null;

生成二维码方法,增加定位点着色参数(System.Drawing.Color),效果如下:

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/// <summary>
/// 生成二维码
/// </summary>
/// <param name="Content">内容文本</param>
/// <param name="QRCodeEncodeMode">二维码编码方式</param>
/// <param name="QRCodeErrorCorrect">纠错码等级</param>
/// <param name="QRCodeVersion">二维码版本号 0-40</param>
/// <param name="QRCodeScale">每个小方格的预设宽度(像素),正整数</param>
/// <param name="size">图片尺寸(像素),0表示不设置</param>
/// <param name="border">图片白边(像素),当size大于0时有效</param>
/// <returns></returns>
public System.Drawing.Image CreateQRCode(string Content, QRCodeEncoder.ENCODE_MODE QRCodeEncodeMode, QRCodeEncoder.ERROR_CORRECTION QRCodeErrorCorrect, int QRCodeVersion, int QRCodeScale, int size, int border, Color codeEyeColor)
{
    QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
    qrCodeEncoder.QRCodeEncodeMode = QRCodeEncodeMode;
    qrCodeEncoder.QRCodeErrorCorrect = QRCodeErrorCorrect;
    qrCodeEncoder.QRCodeScale = QRCodeScale;
    qrCodeEncoder.QRCodeVersion = QRCodeVersion;
      
    System.Drawing.Image image = qrCodeEncoder.Encode(Content);
      
    #region 根据设定的目标图片尺寸调整二维码QRCodeScale设置,并添加边框
    if (size > 0)
    {
        //当设定目标图片尺寸大于生成的尺寸时,逐步增大方格尺寸
        #region 当设定目标图片尺寸大于生成的尺寸时,逐步增大方格尺寸
        while (image.Width < size)
        {
            qrCodeEncoder.QRCodeScale++;
            System.Drawing.Image imageNew = qrCodeEncoder.Encode(Content);
            if (imageNew.Width < size)
            {
                image = new System.Drawing.Bitmap(imageNew);
                imageNew.Dispose();
                imageNew = null;
            }
            else
            {
                qrCodeEncoder.QRCodeScale--; //新尺寸未采用,恢复最终使用的尺寸
                imageNew.Dispose();
                imageNew = null;
                break;
            }
        }
        #endregion
          
        //当设定目标图片尺寸小于生成的尺寸时,逐步减小方格尺寸
        #region 当设定目标图片尺寸小于生成的尺寸时,逐步减小方格尺寸
        while (image.Width > size && qrCodeEncoder.QRCodeScale > 1)
        {
            qrCodeEncoder.QRCodeScale--;
            System.Drawing.Image imageNew = qrCodeEncoder.Encode(Content);
            image = new System.Drawing.Bitmap(imageNew);
            imageNew.Dispose();
            imageNew = null;
            if (image.Width < size)
            {
                break;
            }
        }
        #endregion
  
        //根据参数设置二维码图片白边的最小宽度(按需缩小)
        #region 根据参数设置二维码图片白边的最小宽度
        if (image.Width <= size && border > 0)
        {
            while (image.Width <= size && size - image.Width < border * 2 && qrCodeEncoder.QRCodeScale > 1)
            {
                qrCodeEncoder.QRCodeScale--;
                System.Drawing.Image imageNew = qrCodeEncoder.Encode(Content);
                image = new System.Drawing.Bitmap(imageNew);
                imageNew.Dispose();
                imageNew = null;
            }
        }
        #endregion
          
        //已经确认二维码图像,为图像染色修饰
        if (true)
        {
            //定位点方块边长
            int beSize = qrCodeEncoder.QRCodeScale * 3;
              
            int bep1_l = qrCodeEncoder.QRCodeScale * 2;
            int bep1_t = qrCodeEncoder.QRCodeScale * 2;
              
            int bep2_l = image.Width - qrCodeEncoder.QRCodeScale * 5 - 1;
            int bep2_t = qrCodeEncoder.QRCodeScale * 2;
              
            int bep3_l = qrCodeEncoder.QRCodeScale * 2;
            int bep3_t = image.Height - qrCodeEncoder.QRCodeScale * 5 - 1;
              
            int bep4_l = image.Width - qrCodeEncoder.QRCodeScale * 7 - 1;
            int bep4_t = image.Height - qrCodeEncoder.QRCodeScale * 7 - 1;
              
            System.Drawing.Graphics graphic0 = System.Drawing.Graphics.FromImage(image);
              
            // Create solid brush.
            SolidBrush blueBrush = new SolidBrush(codeEyeColor);
              
            // Fill rectangle to screen.
            graphic0.FillRectangle(blueBrush, bep1_l, bep1_t, beSize, beSize);
            graphic0.FillRectangle(blueBrush, bep2_l, bep2_t, beSize, beSize);
            graphic0.FillRectangle(blueBrush, bep3_l, bep3_t, beSize, beSize);
            graphic0.FillRectangle(blueBrush, bep4_l, bep4_t, qrCodeEncoder.QRCodeScale, qrCodeEncoder.QRCodeScale);
        }
          
        //当目标图片尺寸大于二维码尺寸时,将二维码绘制在目标尺寸白色画布的中心位置
        #region 如果目标尺寸大于生成的图片尺寸,将二维码绘制在目标尺寸白色画布的中心位置
        if (image.Width < size)
        {
            //新建空白绘图
            System.Drawing.Bitmap panel = new System.Drawing.Bitmap(size, size);
            System.Drawing.Graphics graphic0 = System.Drawing.Graphics.FromImage(panel);
            int p_left = 0;
            int p_top = 0;
            if (image.Width <= size) //如果原图比目标形状宽
            {
                p_left = (size - image.Width) / 2;
            }
            if (image.Height <= size)
            {
                p_top = (size - image.Height) / 2;
            }
              
            //将生成的二维码图像粘贴至绘图的中心位置
            graphic0.DrawImage(image, p_left, p_top, image.Width, image.Height);
            image = new System.Drawing.Bitmap(panel);
            panel.Dispose();
            panel = null;
            graphic0.Dispose();
            graphic0 = null;
        }
        #endregion
    }
    #endregion
    return image;
}
原文地址:https://www.cnblogs.com/raincedar/p/7452174.html