自己动手打造ajax图片上传(网上没有的)_AJAX相关_

<%@ webhandler Language="C#" class="Upload" %> 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) { 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 = aspxUrl + "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 = 1000000; this.context = context; 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。"); } 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); } String newFileName = DateTime.Now.ToString("yyyyMMddHHmmss_ffff", DateTimeFormatInfo.InvariantInfo) + fileExt; String filePath = dirPath + newFileName; imgFile.SaveAs(filePath); String fileUrl = saveUrl + newFileName; Hashtable hash = new Hashtable(); hash["error"] = 0; hash["url"] = fileUrl; context.Response.AddHeader("Content-Type", "text/html; charset=UTF-8"); context.Response.Write(JsonMapper.ToJson(hash)); context.Response.End(); } 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; } } }