使用Graphics合成带二维码和头像的分享图(小程序分享、App分享)

//分享的海报背景图片 使用本地图片文件   string path = Server.MapPath("/Content/images/backimg.jpg"); Image imgSrc = Image.FromFile(path);   //将文件加载成图片格式  //二维码图片文件  使用远程图片文件   var qr_url="http://xxxxxx:8001/Images/qrimg.jpg"; Image qrCodeImage= ReduceImage(qr_url, 122, 122);  //头像文件  使用远程图片文件   var headurl="http://xxxxxx:8001/Images/header.jpg"; Image headImage=  ReduceImage(headurl, 59, 59);  //开始合成图片   声明画图工具 using (Graphics g = Graphics.FromImage(imgSrc))   {       //画推广二维码 声明起始坐标点       //从x轴30像素处、y轴的40像素处开始画       int qr_x = 30,qr_y = 40;           //指定二维码在合成图上显示的坐标和区域大小        Rectangle destRect = new Rectangle(qr_x, qr_y, qrCodeImage.Width, qrCodeImage.Height);         //在destRect声明的区域内，开始绘制二维码        Rectangle srcRect = new Rectangle(0, 0, qrCodeImage.Width, qrCodeImage.Height);         //开始绘制  GraphicsUnit.Pixel 表示以像素为单位        g.DrawImage(qrCodeImage, destRect, srcRect, GraphicsUnit.Pixel);          //画头像 裁剪头像(圆形)        Image header = CutEllipse(titleImage, new Size(59, 59));           int w = header.Width, h = header.Height;  //图片宽高        int x = 24, y = 982;   //图片坐标         g.DrawImage(header,                         new Rectangle(x, y, w, h),                         new Rectangle(0, 0, w, h),                         GraphicsUnit.Pixel);          //画昵称  思源黑体 CN 常规  字体大小18  粗体         Font font = new Font("Source Han Sans CN Regular", 18, FontStyle.Bold, GraphicsUnit.Pixel);         Color fontColor = (Color)new ColorConverter().ConvertFromString("#999999");         g.DrawString("张三", font, new SolidBrush(fontColor), 100, 990);  //坐标点 x=100  y=990          //画其他文本  思源黑体 CN 常规         var othertext = "邀请您看直播";         g.DrawString(othertext, font, new SolidBrush(fontColor), 101, 1014);  //坐标点 x=100  y=990          header.Dispose();         g.Dispose(); }  //获取系统编码类型数组,包含了jpeg,bmp,png,gif,tiff int quality = 50; //图像质量 1 - 100的范围 ImageCodecInfo[] icis = ImageCodecInfo.GetImageEncoders(); ImageCodecInfo ici = null; foreach (ImageCodecInfo i in icis) {     if (i.MimeType == "image/jpeg" || i.MimeType == "image/bmp" || i.MimeType == "image/png" || i.MimeType == "image/gif")      {         ici = i;      } } EncoderParameters ep = new EncoderParameters(1); ep.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);  //将图片转换成二进制流 MemoryStream ms = new MemoryStream();//读取字节流 imgSrc.Save(ms, ici, ep); var buffer = ms.GetBuffer();  //图片流  ms.Dispose(); imgSrc.Dispose(); qrCodeImage.Dispose(); headImage.Dispose(); ep.Dispose();

 1         /// <summary>  2         /// 缩小/放大图片    3         /// </summary>  4         /// <param name="url">图片网络地址</param>  5         /// <param name="toWidth">缩小/放大宽度</param>  6         /// <param name="toHeight">缩小/放大高度</param>  7         /// <returns></returns>  8         private static Image ReduceImage(string url, int toWidth, int toHeight, string param = null)  9         { 10             try 11             { 12                 Stream responseStream = null; 13                 if (param != null)   //post请求 14                 { 15                     var intResult = HttpHelper.HttpClientPost(url, param, out responseStream); 16                 } 17                 else 18                 { 19                     WebRequest request = WebRequest.Create(url); 20                     WebResponse response = request.GetResponse(); 21                     responseStream = response.GetResponseStream(); 22                 } 23                 if (responseStream == null) 24                 { 25                     return null; 26                 } 27  28                 Image originalImage = Image.FromStream(responseStream); 29                 if (toWidth <= 0 && toHeight <= 0)  //返回原图 30                 { 31                     return originalImage; 32                 } 33                 else if (toWidth > 0 && toHeight > 0)  ////给了宽*高 如果原始小，则返回原图 34                 { 35                     if (originalImage.Width < toWidth && originalImage.Height < toHeight) 36                         return originalImage; 37                 } 38                 else if (toWidth <= 0 && toHeight > 0)  //给了高,根据高计算宽，得出正方形图片 39                 { 40                     if (originalImage.Height < toHeight) 41                         return originalImage; 42                     toWidth = originalImage.Width * toHeight / originalImage.Height; 43                 } 44                 else if (toHeight <= 0 && toWidth > 0)  //给了宽,根据宽计算高，得出正方形图片 45                 { 46                     if (originalImage.Width < toWidth) 47                         return originalImage; 48                     toHeight = originalImage.Height * toWidth / originalImage.Width; 49                 } 50                 Image toBitmap = new Bitmap(toWidth, toHeight);   //定义一个指定大小的画布背景 51                 using (Graphics g = Graphics.FromImage(toBitmap))   //定义画图工具，使用画图工具加载画布背景,开始在画布上作图 52                 { 53                     //图片缩放时使用 54                     g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighSpeed;  //高速度、低质量 55                     g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; //图像缩放质量 56                     //生成图片时使用 57                     g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;  //图片呈现质量，即消除锯齿 58                     g.Clear(Color.Transparent);  //清除背景色，并设置颜色为透明 Color.Transparent 59                     g.DrawImage(originalImage, 60                                 new Rectangle(0, 0, toWidth, toHeight), 61                                 new Rectangle(0, 0, originalImage.Width, originalImage.Height), 62                                 GraphicsUnit.Pixel); 63                     originalImage.Dispose(); 64                     responseStream.Dispose(); 65                     g.Dispose(); 66                     return toBitmap; 67                 } 68             } 69             catch (Exception ex) 70             { 71                 throw; 72             } 73         }

 1         /// <summary>  2         /// 画圆形头像  3         /// </summary>  4         /// <param name="img">待裁剪的图片</param>  5         /// <param name="size">裁剪大小</param>  6         /// <returns></returns>  7         private static Image CutEllipse(Image img, Size size)  8         {  9             try 10             { 11                 var rec = new Rectangle(0, 0, size.Width, size.Height); //声明位置和大小 12                 Bitmap bitmap = new Bitmap(size.Width, size.Height);  //声明画布并指定大小 13                 Pen p = new Pen(Color.Transparent);  //声明透明色画笔 14                 using (Graphics g = Graphics.FromImage(bitmap)) 15                 { 16                     using (TextureBrush br = new TextureBrush(img, rec))  //声明画刷 17                     { 18                         g.SmoothingMode = SmoothingMode.HighQuality;  //使绘图质量最高，即消除锯齿 19                         g.InterpolationMode = InterpolationMode.HighQualityBicubic; 20                         g.CompositingQuality = CompositingQuality.HighQuality; 21  22                         g.FillEllipse(br, rec);  //根据指定大小和位置填充圆形 23                         g.DrawEllipse(p, rec);   //画圆形图 24                         br.Dispose(); 25                     } 26                     g.Dispose(); 27                 } 28                 return bitmap; 29             } 30             catch (Exception ex) 31             { 32                 throw; 33             } 34         }