时间:2021-11-16 16:33:02 | 栏目:.NET代码 | 点击:次
最近需要将一张图片上传并按指定位置剪裁,后来在网上找了一个剪裁图片的插件,但是只有前台没有后端,然后我各种百度,并最终完成,特此写一篇博客略表纪念。
下面是代码:
HttpPostedFile file = context.Request.Files["avatar_file"]; string datasize = context.Request.Params["avatar_data"]; //{"x":30.003846153846148,"y":16.715384615384625,"height":300.8,"width":300.8,"rotate":0} 剪裁之后参数 JavaScriptSerializer jss = new JavaScriptSerializer(); ImgSize imagesize = jss.Deserialize<ImgSize>(datasize); byte[] FileByte = SetFileToByteArray(file);//图片数组 string strtExtension = System.IO.Path.GetExtension(file.FileName);//图片格式 MemoryStream ms1 = new MemoryStream(FileByte); Bitmap sBitmap = (Bitmap)Image.FromStream(ms1); Rectangle section = new Rectangle(new Point(imagesize.ToInt(imagesize.x), imagesize.ToInt(imagesize.y)), new Size(imagesize.ToInt(imagesize.width), imagesize.ToInt(imagesize.height))); Bitmap CroppedImage = MakeThumbnailImage(sBitmap, section.Width, section.Height, section.Width, section.Height, section.X, section.Y);
上面代码中用到我自己创建了一个ImgSize类,代码如下:
class ImgSize { //{"x":30.003846153846148,"y":16.715384615384625,"height":300.8,"width":300.8,"rotate":0} public double x { get; set; } public double y { get; set; } public double width { get; set; } public double height { get; set; } public int rotate { get; set; } public int ToInt(double doubleValue) { return Convert.ToInt32(doubleValue); } }
上面代码中使用到的几个方法:
文件转化:
/// <summary> /// 将From表单file文件转化为byte数组 /// </summary> /// <param name="File">from提交文件流</param> /// <returns></returns> private byte[] SetFileToByteArray(HttpPostedFile File) { Stream stream = File.InputStream; byte[] AyyayByte = new byte[File.ContentLength]; stream.Read(AyyayByte, 0, File.ContentLength); stream.Close(); return AyyayByte; }
核心剪裁方法:
/// <summary> /// 裁剪图片并保存 /// </summary> /// <param name="Image">图片信息</param> /// <param name="maxWidth">缩略图宽度</param> /// <param name="maxHeight">缩略图高度</param> /// <param name="cropWidth">裁剪宽度</param> /// <param name="cropHeight">裁剪高度</param> /// <param name="X">X轴</param> /// <param name="Y">Y轴</param> public static Bitmap MakeThumbnailImage(Image originalImage, int maxWidth, int maxHeight, int cropWidth, int cropHeight, int X, int Y) { Bitmap b = new Bitmap(cropWidth, cropHeight); try { using (Graphics g = Graphics.FromImage(b)) { //清空画布并以透明背景色填充 g.Clear(Color.Transparent); //在指定位置并且按指定大小绘制原图片的指定部分 g.DrawImage(originalImage, new Rectangle(0, 0, cropWidth, cropHeight), X, Y, cropWidth, cropHeight, GraphicsUnit.Pixel); Image displayImage = new Bitmap(b, maxWidth, maxHeight); displayImage.Save("E:\\cutimg.jpg", System.Drawing.Imaging.ImageFormat.Jpeg); Bitmap bit = new Bitmap(b, maxWidth, maxHeight); return bit; } } catch (System.Exception e) { throw e; } finally { originalImage.Dispose(); b.Dispose(); } }
最后的结果是把存到了E盘根目录下面