详细QRCode生成二维码和下载实现案例

时间:2022-12-14 20:29:22
  1 using System;
  2 using System.Collections.Generic;
  3 using System.Linq;
  4 using System.Web;
  5 using ThoughtWorks.QRCode.Codec;
  6 using System.Drawing;
  7 using System.Drawing.Imaging;
  8 using Game.Utils;
  9 using System.Drawing.Drawing2D;
 10 using Game.Facade;
 11 using System.Net;
 12 using System.IO;
 13 
 14 namespace Game.Web.WS
 15 {
 16     /// <summary>
 17     /// QRCode 的摘要说明
 18     /// </summary>
 19     public class QRCode : IHttpHandler
 20     {
 21 
 22         public void ProcessRequest(HttpContext context)
 23         {
 24             GetQRCode(context);
 25         }
 26 
 27         /// <summary>
 28         /// 绘制二维码
 29         /// </summary>
 30         /// <param name="context"></param>
 31         private void GetQRCode(HttpContext context)
 32         {
 33             string encodeData = GameRequest.GetQueryString("qt");
 34             string icoURL = GameRequest.GetQueryString("qm");
 35             int width = GameRequest.GetQueryInt("qs", 0);
 36             if (encodeData != string.Empty)
 37             {
 38                 calQrcode(encodeData, icoURL, width, context);
 39             }
 40         }
 41 
 42         /// <summary>
 43         /// 按照指定的大小绘制二维码
 44         /// </summary>
 45         /// <param name="sData"></param>
 46         /// <param name="width"></param>
 47         /// <returns></returns>
 48         private void calQrcode(string sData, string icoURL, int size, HttpContext context)
 49         {
 50             //二维码版本,大小获取
 51             Color qrCodeBackgroundColor = Color.White;
 52             Color qrCodeForegroundColor = Color.Black;
 53             int length = System.Text.Encoding.UTF8.GetBytes(sData).Length;
 54 
 55             //生成二维码数据
 56             QRCodeEncoder qrCodeEncoder = new QRCodeEncoder();
 57             qrCodeEncoder.QRCodeEncodeMode = QRCodeEncoder.ENCODE_MODE.BYTE;
 58             qrCodeEncoder.QRCodeErrorCorrect = QRCodeEncoder.ERROR_CORRECTION.M;//使用M纠错级别
 59             qrCodeEncoder.QRCodeVersion = 0;
 60             var encodedData = qrCodeEncoder.Encode(sData, System.Text.Encoding.UTF8);
 61 
 62             //绘制图片
 63             int x = 0, y = 0;
 64             int w = 0, h = 0;
 65             // 二维码矩阵单边数据点数目
 66             int count = encodedData.Length;
 67             // 获取单个数据点边长
 68             double sideLength = Convert.ToDouble(size) / count;
 69             // 初始化背景色画笔
 70             SolidBrush backcolor = new SolidBrush(qrCodeBackgroundColor);
 71             // 初始化前景色画笔
 72             SolidBrush forecolor = new SolidBrush(qrCodeForegroundColor);
 73             // 定义画布
 74             Bitmap image = new Bitmap(size, size);
 75             // 获取GDI+绘图图画
 76             Graphics graph = Graphics.FromImage(image);
 77             // 先填充背景色
 78             graph.FillRectangle(backcolor, 0, 0, size, size);
 79 
 80             // 变量数据矩阵生成二维码
 81             for (int row = 0; row < count; row++)
 82             {
 83                 for (int col = 0; col < count; col++)
 84                 {
 85                     // 计算数据点矩阵起始坐标和宽高
 86                     x = Convert.ToInt32(Math.Round(col * sideLength));
 87                     y = Convert.ToInt32(Math.Round(row * sideLength));
 88                     w = Convert.ToInt32(Math.Ceiling((col + 1) * sideLength) - Math.Floor(col * sideLength));
 89                     h = Convert.ToInt32(Math.Ceiling((row + 1) * sideLength) - Math.Floor(row * sideLength));
 90 
 91                     // 绘制数据矩阵
 92                     graph.FillRectangle(encodedData[col][row] ? forecolor : backcolor, x, y, w, h);
 93                 }
 94             }
 95 
 96             //添加LOGO
 97             string path = context.Server.MapPath("/favicon.ico");            
 98             Bitmap logoImage = null;
 99             FileInfo fileInfo = new FileInfo(path);
100             if (fileInfo.Exists)
101             {
102                 logoImage = new Bitmap(path);
103             }
104             if (icoURL != "")
105             {
106                 HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.Create(icoURL);
107                 try
108                 {
109                     HttpWebResponse webReponse = (HttpWebResponse)webRequest.GetResponse();
110                     if (webReponse.StatusCode == HttpStatusCode.OK)
111                     {
112                         using (Stream stream = webReponse.GetResponseStream())
113                         {
114                             Image img = Image.FromStream(stream);
115                             logoImage = new Bitmap(img);
116                             img.Dispose();
117                         }
118                     }
119                 }
120                 catch { }
121             }
122             if (logoImage != null)
123             {
124                 image = CoverImage(image, logoImage, graph);
125                 logoImage.Dispose();            
126             }         
127             //输出
128             System.IO.MemoryStream ms = new System.IO.MemoryStream();
129             image.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
130             context.Response.ClearContent();
131             context.Response.ContentType = "image/png";
132             context.Response.AddHeader("Content-Disposition", "attachment;  filename=" + HttpUtility.UrlEncode("QRCodeImg.png", System.Text.Encoding.UTF8));
133             context.Response.BinaryWrite(ms.ToArray());
134             context.Response.Flush();
135             context.Response.End();
136             image.Dispose();
137         }
138 
139         /// <summary>
140         /// 层叠图片
141         /// </summary>
142         /// <param name="original">原始图片(目前只支持正方形)</param>
143         /// <param name="image">层叠图片(目前只支持正方形)</param>
144         /// <returns>处理以后的图片</returns>
145         private Bitmap CoverImage(Bitmap original, Bitmap image, Graphics graph = null)
146         {
147             //缩放附加图片
148             int sideSLen = original.Width;
149             int sideTLen = sideSLen / 4;
150             image = ResizeImage(image, sideTLen, sideTLen);
151 
152             // 获取GDI+绘图图画
153             graph = graph == null ? Graphics.FromImage(original) : graph;
154 
155             // 将附加图片绘制到原始图*
156             graph.DrawImage(image, (original.Width - sideTLen) / 2, (original.Height - sideTLen) / 2, sideTLen, sideTLen);
157 
158             // 释放GDI+绘图图画内存
159             graph.Dispose();
160 
161             // 返回处理结果
162             return original;
163         }
164 
165         /// <summary>
166         /// 图片缩放
167         /// </summary>
168         /// <param name="bmp">原始Bitmap</param>
169         /// <param name="newW">新的宽度</param>
170         /// <param name="newH">新的高度</param>
171         /// <returns>处理以后的图片</returns>
172         private Bitmap ResizeImage(Bitmap original, int width, int height)
173         {
174             try
175             {
176                 Bitmap image = new Bitmap(width, height);
177                 Graphics graph = Graphics.FromImage(image);
178                 // 插值算法的质量
179                 graph.CompositingQuality = CompositingQuality.HighQuality;
180                 graph.SmoothingMode = SmoothingMode.HighQuality;
181                 graph.InterpolationMode = InterpolationMode.HighQualityBicubic;
182                 graph.DrawImage(original, new Rectangle(0, 0, width, height),
183                     new Rectangle(0, 0, original.Width, original.Height), GraphicsUnit.Pixel);
184                 graph.Dispose();
185                 return image;
186             }
187             catch
188             {
189                 return null;
190             }
191         }       
192 
193         public bool IsReusable
194         {
195             get
196             {
197                 return false;
198             }
199         }
200     }
201 }