C#结合imgareaselect生成缩略图并截取图片

</pre><pre name="code" class="csharp">-----前端html<script type="text/javascript" src="@Url.Content("~/scripts/jquery-1.7.1.min.js")"></script><link rel="stylesheet" type="text/css" href="@Url.Content("~/contentpc/css/imgareaselect-default.css")"/><div class="popup" id="cutDiv">    @using (Html.BeginForm("avgupload", "user", FormMethod.Post, new { id = "form2" }))    {        <dl>            <dt>头像截取<a href="###" class="btn_close transition_a" id="Cut_close">关闭</a></dt>            <div style="background-color: #f6f6f6">                <dd>                    <div class="l_560" style="width: 600px;">                        <div style="float: left; min-width: 400px; text-align: center">                        <div style="font-size: 16px; color: #888; text-align: center">                                鼠标划拉图片选择区域↖↘</div>                            <img alt="" id="oldAvg" width="360" height="360" src="@(string.IsNullOrEmpty(Model.Avg) ? Url.Content("~/contentpc/images/tool/photo_80.png") : Url.Content("~/content/accessory/" + Model.Avg))"/>                        </div>                        <div style="float: right;">                            <div style="font-size: 16px; color: #888; text-align: center">                                预览</div>                            <div id="preview" style="width: 180px; height: 180px; overflow: hidden;">                                <img src="@(string.IsNullOrEmpty(Model.Avg) ? Url.Content("~/contentpc/images/tool/photo_80.png") : Url.Content("~/content/accessory/" + Model.Avg))" >                            </div>                            <span style="text-align: center">尺寸：180 x 180</span>                            <input type="hidden" name="x1" id="x1" value="0" />                            <input type="hidden" name="y1" id="y1" value="0" />                            <input type="hidden" name="x2" id="x2" value="180" />                            <input type="hidden" name="y2" id="y2" value="180" />                        </div>                    </div>                    <br />                    <input type="submit" value="保存" class="blue_btn transition_a round_s" style="width: 100px;                        padding: 0.5em 0 0 0" />                </dd>            </div>        </dl>    }</div>------------前端脚本<script>$(document).ready(function () {        $('#oldAvg').imgAreaSelect({            aspectRatio: '1:1',            fadeSpeed: 1200,            autoHide: true,            show: false,            handles: false,            onSelectChange: preview        });        function preview(img, selection) {            if (!selection.width || !selection.height)                return;            $('input[name="x1"]').val(selection.x1);            $('input[name="y1"]').val(selection.y1);            $('input[name="x2"]').val(selection.x2);            $('input[name="y2"]').val(selection.y2);            var scaleX = 180 / selection.width;            var scaleY = 180 / selection.height;            $('#preview img').css({                width: Math.round(scaleX * 360),                height: Math.round(scaleY * 360),                marginLeft: -Math.round(scaleX * selection.x1),                marginTop: -Math.round(scaleY * selection.y1)            });        }</script>------------服务器端[HttpPost]        public ActionResult AvgUpload()        {            TUser model = System.Web.HttpContext.Current.Session["LoginUser"] as TUser;            TUser user = TUserRepository.GetById(model.ID);            try            {                int x1 = Convert.ToInt32(Request["x1"]);                int y1 = Convert.ToInt32(Request["y1"]);                int x2 = Convert.ToInt32(Request["x2"]);                int y2 = Convert.ToInt32(Request["y2"]);                int width = x2 - x1;                int height = y2 - y1;                string SavePath = System.Web.HttpContext.Current.Server.MapPath("~/Content/accessory/");//获取图片存放路径                string oldAvgPath = SavePath + user.Avg;//获取原头像图片                string Thumbnail = Guid.NewGuid().ToString("N") + Path.GetExtension(user.Avg);                string ThumbnailPath = SavePath + Thumbnail;                string newAvg = Guid.NewGuid().ToString("N") + Path.GetExtension(user.Avg);//生成新的图片                string newAvgPath = SavePath + newAvg;                if (!string.IsNullOrEmpty(user.Avg))                {                    //-------------------------------------------------------------------原始图片                    System.Drawing.Image avgImage = Image.FromFile(oldAvgPath);                    //System.Drawing.Image ChangeImage = sourceImage.GetThumbnailImage(360, 360, () => { return false; }, System.IntPtr.Zero);                    int AvgWidth = avgImage.Width;                    int AvgHeight = avgImage.Height;                    //生成缩略图                    SaveThumbnail(avgImage, 360, 360, ThumbnailPath, user.Avg, Path.GetExtension(user.Avg), AvgWidth, AvgHeight);                    System.Drawing.Image sourceImage = Image.FromFile(ThumbnailPath);                    //-------------------------------------------------------------------裁剪的区域                    Rectangle fromR = new Rectangle(x1, y1, width, height);                    //-------------------------------------------------------------------裁剪出来的图要放在画布的哪个位置                    Rectangle toR = new Rectangle(0, 0, width, height);                    //-------------------------------------------------------------------要当画布的Bitmap物件                    System.Drawing.Bitmap bitmap = new System.Drawing.Bitmap(width, height);                    //-------------------------------------------------------------------产生画布                    System.Drawing.Graphics g = Graphics.FromImage(bitmap);                    //-------------------------------------------------------------------清空画布，背景白色                    g.Clear(Color.White);                    //-------------------------------------------------------------------剪裁                    g.DrawImage(sourceImage, toR, fromR, GraphicsUnit.Pixel);                    //裁剪完成，存盘                    bitmap.Save(newAvgPath, ImageFormat.Jpeg);                    //释放资源                    g.Dispose();                    bitmap.Dispose();                    sourceImage.Dispose();                    avgImage.Dispose();                    //ChangeImage.Dispose();                }                user.Avg = newAvg;                TUserRepository.Update(user);                unitOfWork.Commit();                System.IO.File.Delete(oldAvgPath);//把原始档删除                System.IO.File.Delete(ThumbnailPath);//把原始档删除                return RedirectToAction("avgindex", "user");            }            catch            {                return Content("<script>alert('系统出错，请重试！');window.location.href='/user/avgindex'</script>");            }        }        private void SaveThumbnail(Image originBitmap, int Imgwidth, int Imgheight, string physicalPath, string filename, string extension, int initWidth, int initHeight)        {            using (var newImage = new Bitmap(Imgwidth, Imgheight))            {                using (var graphic = GetGraphic(originBitmap, newImage))                {                    graphic.DrawImage(originBitmap, new Rectangle(0, 0, 360, 360), new Rectangle(0, 0, initWidth, initHeight), GraphicsUnit.Pixel);                    using (var encoderParameters = new EncoderParameters(1))                    {                        encoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);                        newImage.Save(physicalPath,                                    ImageCodecInfo.GetImageEncoders()                                        .Where(x => x.FilenameExtension.Contains(extension.ToUpperInvariant()))                                        .FirstOrDefault(),                                    encoderParameters);                    }                }            }        }        private Graphics GetGraphic(Image originImage, Bitmap newImage)        {            newImage.SetResolution(originImage.HorizontalResolution, originImage.VerticalResolution);            var graphic = Graphics.FromImage(newImage);            graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;            graphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;            graphic.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;            graphic.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;            graphic.Clear(Color.White);            return graphic;        }