详细QRCode生成二维码和下载实现案例

  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 }