1.下载ThoughtWorks.QRCode引用并添加在工程中
2.在实现类QRCodeEncoderDemo中引入Dll，添加方法

using System;using System.Collections.Generic;using System.Drawing;using System.Drawing.Drawing2D;using System.Linq;using System.Web;using ThoughtWorks.QRCode;using ThoughtWorks.QRCode.Codec;namespace WebApplication3{public class QRCodeEncoderDemo{/// <summary>  /// 生成二维码.  /// </summary>  /// <param name="data">需要添加进去的文本</param>  /// <returns></returns>  public System.Drawing.Image GCode(String data){QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;qrCodeEncoder.QRCodeScale = 5;qrCodeEncoder.QRCodeVersion = 7;qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.L;var pbImg = qrCodeEncoder.Encode(data, System.Text.Encoding.UTF8);var width = pbImg.Width / 10;var dwidth = width * 2;Bitmap bmp = new Bitmap(pbImg.Width + dwidth, pbImg.Height + dwidth);Graphics g = Graphics.FromImage(bmp);var c = System.Drawing.Color.White;g.FillRectangle(new SolidBrush(c), 0, 0, pbImg.Width + dwidth, pbImg.Height + dwidth);g.DrawImage(pbImg, width, width);g.Dispose();return bmp;}/// <summary>  /// 调用此函数后使此两种图片合并，类似相册，有个  /// 背景图，中间贴自己的目标图片  /// </summary>  /// <param name="sourceImg">粘贴的源图片</param>  /// <param name="destImg">粘贴的目标图片</param>  public static System.Drawing.Image CombinImage(System.Drawing.Image imgBack, string destImg){System.Drawing.Image img = System.Drawing.Image.FromFile(destImg);        //照片图片    if (img.Height != 50 || img.Width != 50){img = KiResizeImage(img, 60, 60, 0);}Graphics g = Graphics.FromImage(imgBack);//g.DrawImage(imgBack, 0, 0, 相框宽, 相框高); g.DrawImage(imgBack, 0, 0, imgBack.Width, imgBack.Height);        //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;}/// <summary>  /// Resize图片  /// </summary>  /// <param name="bmp">原始Bitmap</param>  /// <param name="newW">新的宽度</param>  /// <param name="newH">新的高度</param>  /// <param name="Mode">保留着，暂时未用</param>  /// <returns>处理以后的图片</returns>  public static System.Drawing.Image KiResizeImage(System.Drawing.Image bmp, int newW, int newH, int Mode){try{System.Drawing.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;}}}}

 3.生成二维码(psb.jpg可自选，此处默认)

protected void BtnCreate_Click(object sender, EventArgs e){         QRCodeEncoderDemo qrc = new QRCodeEncoderDemo();//生成二维码图片System.Drawing.Image ImageBack=qrc.GCode(this.txtstr.Text.ToString());string DestImg = Server.MapPath(@"~/Image/psb.jpg");System.Drawing.Image Img = QRCodeEncoderDemo.CombinImage(ImageBack, DestImg);string filename = DateTime.Now.ToString("yyyyMMddhhmmss") + ".jpg";Img.Save(Server.MapPath(@"~/Image/") + filename);this.Img.ImageUrl = "~/Image/" + filename;}

  4.解析二维码

protected void Button1_Click(object sender, EventArgs e){QRCodeDecoder decoder = new QRCodeDecoder();Bitmap bt = new Bitmap(Server.MapPath(@"~/Image/"+this.Img.ImageUrl.Substring(this.Img.ImageUrl.LastIndexOf('/'))));string decodedString = decoder.decode(new QRCodeBitmapImage(bt),Encoding.UTF8);this.TxtContent.Text = decodedString;}