主题: ASP.NET下生成缩略图,不能返回图片地址在线求解 |
作者: 爱喇叭网, 发布日期: 2012-04-22 10:44:12, 浏览数: 5036 |
图片上传功能调用的是:upload_json.ashx
using System; using System.Collections; using System.Web; using System.IO; using System.Globalization; using LitJson; public class Upload : IHttpHandler { private HttpContext context; public void ProcessRequest(HttpContext context) { //获得文件名 //String aspxUrl = context.Request.Path.Substring(0, context.Request.Path.LastIndexOf("/") + 1); //文件保存目录路径 String savePath = "/attached/"; //文件保存目录URL String saveUrl = "/attached/"; //定义允许上传的文件扩展名 Hashtable extTable = new Hashtable(); extTable.Add("image", "gif,jpg,jpeg,png,bmp"); extTable.Add("flash", "swf,flv"); extTable.Add("media", "swf,flv,mp3,wav,wma,wmv,mid,avi,mpg,asf,rm,rmvb"); extTable.Add("file", "doc,docx,xls,xlsx,ppt,htm,html,txt,zip,rar,gz,bz2"); //最大文件大小 int maxSize = 52428800; this.context = context; //获取文件 HttpPostedFile imgFile = context.Request.Files["imgFile"]; if (imgFile == null) { showError("请选择文件。"); } String dirPath = context.Server.MapPath(savePath); if (!Directory.Exists(dirPath)) { showError("上传目录不存在。"); } //获取文件类型 String dirName = context.Request.QueryString["dir"]; if (String.IsNullOrEmpty(dirName)) { dirName = "image"; } if (!extTable.ContainsKey(dirName)) { showError("目录名不正确。"); } String fileName = imgFile.FileName; String fileExt = Path.GetExtension(fileName).ToLower(); if (imgFile.InputStream == null || imgFile.InputStream.Length > maxSize) { showError("上传文件大小超过限制。"); } if (String.IsNullOrEmpty(fileExt) || Array.IndexOf(((String)extTable[dirName]).Split(','), fileExt.Substring(1).ToLower()) == -1) { showError("上传文件扩展名是不允许的扩展名。\n只允许" + ((String)extTable[dirName]) + "格式。"); } //创建文件夹 dirPath += dirName + "/"; saveUrl += dirName + "/"; if (!Directory.Exists(dirPath)) { Directory.CreateDirectory(dirPath); } String ymd = DateTime.Now.ToString("yyyyMMdd", DateTimeFormatInfo.InvariantInfo); dirPath += ymd + "/"; saveUrl += ymd + "/"; if (!Directory.Exists(dirPath)) { Directory.CreateDirectory(dirPath); } //生成文件名 String newFileName = DateTime.Now.ToString("yyyyMMddHHmmss_ffff", DateTimeFormatInfo.InvariantInfo) + fileExt; //文件保存的物理里地址 String filePath = dirPath + newFileName; //保存文件 imgFile.SaveAs(filePath); //文件相对地址 String fileUrl = saveUrl + newFileName; //设置返回信息,返回值是以JSON数组形式返回的,即前面是key,后面是value Hashtable hash = new Hashtable(); hash["error"] = 0; //返回原图的地址 hash["url"] = fileUrl; /* 还可设置多个返回结果,比如图片的宽,高等 如:hash["width"]=100; */ //判断上传的文件类型 if (context.Request.QueryString["dir"] == "image") { //请求中有width这个参数表示图片需要进行处理 if (context.Request.QueryString["width"] != null) { //缩略图相对地址 string thumbfilePath = dirPath + "Thumb" + newFileName; int width=Convert.ToInt32(context.Request.QueryString["width"]); int height=Convert.ToInt32(context.Request.QueryString["height"]); //获得原始图片的宽和高 System.Drawing.Image originalImage = System.Drawing.Image.FromFile(filePath); int ow = originalImage.Width; int oh = originalImage.Height; //如果原图的尺寸比缩略图要求的尺寸小,则不进行任何处理 if (width <= ow && height <= oh) { string smillUrl = fileUrl; //返回缩略图的地址 hash["thumUrl"] = smillUrl; } else { //生成缩略图 if (MakeThumbnail(filePath, thumbfilePath, width, height, "HW")) { string smillUrl = saveUrl + "Thumb" + newFileName; hash["thumUrl"] = smillUrl; } else { showError("生成缩略图失败"); } } } } context.Response.AddHeader("Content-Type", "text/html; charset=UTF-8"); context.Response.Write(JsonMapper.ToJson(hash)); context.Response.End(); } //返回错误消息 private void showError(string message) { Hashtable hash = new Hashtable(); hash["error"] = 1; hash["message"] = message; context.Response.AddHeader("Content-Type", "text/html; charset=UTF-8"); context.Response.Write(JsonMapper.ToJson(hash)); context.Response.End(); } public bool IsReusable { get { return true; } } /// <summary> /// 生成缩略图 /// </summary> /// <param name="originalImagePath">源图路径(物理路径)</param> /// <param name="thumbnailPath">缩略图路径(物理路径)</param> /// <param name="width">缩略图宽度</param> /// <param name="height">缩略图高度</param> /// <param name="mode">生成缩略图的方式</param> public static bool MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode) { System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath); int towidth = width; int toheight = height; int x = 0; int y = 0; int ow = originalImage.Width; int oh = originalImage.Height; switch (mode) { case "HW"://指定高宽缩放(可能变形) break; case "W"://指定宽,高按比例 toheight = originalImage.Height * width / originalImage.Width; break; case "H"://指定高,宽按比例 towidth = originalImage.Width * height / originalImage.Height; break; case "Cut"://指定高宽裁减(不变形) if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight) { oh = originalImage.Height; ow = originalImage.Height * towidth / toheight; y = 0; x = (originalImage.Width - ow) / 2; } else { ow = originalImage.Width; oh = originalImage.Width * height / towidth; x = 0; y = (originalImage.Height - oh) / 2; } break; default: break; } //新建一个bmp图片 System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight); //新建一个画板 System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap); //设置高质量插值法 g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High; //设置高质量,低速度呈现平滑程度 g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality; //清空画布并以透明背景色填充 g.Clear(System.Drawing.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 System.Drawing.Rectangle(0, 0, towidth, toheight), new System.Drawing.Rectangle(x, y, ow, oh), System.Drawing.GraphicsUnit.Pixel); try { //以jpg格式保存缩略图 bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg); return true; } catch (System.Exception e) { return false; throw e; } finally { originalImage.Dispose(); bitmap.Dispose(); g.Dispose(); } } } 好了,原来是里面的js有错误,我不懂js,一点点试出来的!不用日
KindEditor.ready(function(K) { var editor1 = K.create('#TxtContent', { cssPath : '../zzqdeditor/plugins/code/prettify.css', uploadJson : '../zzqdeditor/net/upload_json.ashx', fileManagerJson : '../zzqdeditor/net/file_manager_json.ashx', allowFileManager : true, afterCreate : function() { var self = this; K.ctrl(document, 13, function() { self.sync(); K('form[name=example]')[0].submit(); }); K.ctrl(self.edit.doc, 13, function() { self.sync(); K('form[name=example]')[0].submit(); }); } }); prettyPrint(); }); KindEditor.ready(function (K) { var uploadbutton = K.uploadbutton({ button: K('#uploadButton')[0], //上传的文件类型 fieldName: 'imgFile', //注意后面的参数,dir表示文件类型,width表示缩略图的宽,height表示高 url: '../Editer/asp.net/upload_json.ashx?dir=image&width=65&height=61', afterUpload: function (data) { if (data.error === 0) { alert('图片上传成功'); //取返回值,注意后台设置的key,如果要取原值 //取缩略图地址 var thumUrl = K.formatUrl(data.thumUrl, 'absolute'); //取原图地址 //var url=k.fromUrl(data.Url,'absolute'); K('#txtPic').val(thumUrl); } else { alert(data.message); } }, afterError: function (str) { alert('自定义错误信息: ' + str); } }); uploadbutton.fileBox.change(function (e) { uploadbutton.submit(); }); }); 不过感觉这个还是不太好用!还需要单独传一张生成缩略图,很不方便,如果能够从文章中选一张就好了。 另外需要集成保存远程图片功能,保存远程图片时哪一张当缩略图? 还需要改造! |
作者: 小刚, 发布日期: 2012-08-20 17:21:24 |
关注中,怎么官方没人回答呢,版本升级的教程好像没看到在那里,望告知
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作者: swtseaman, 发布日期: 2012-08-23 00:29:36 |
这个我今天刚搞定,如果需要请Email我 swtseaman@vip.qq.com
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