|
Request.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中央
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 }
|