<%@ Page Language="C#" AutoEventWireup="true" CodePage="65001" %>

<%@ Import Namespace="System" %>
<%@ Import Namespace="System.Collections" %>
<%@ Import Namespace="System.Configuration" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Web" %>
<%@ Import Namespace="System.Web.Security" %>
<%@ Import Namespace="System.Web.UI" %>
<%@ Import Namespace="System.Web.UI.HtmlControls" %>
<%@ Import Namespace="System.Web.UI.WebControls" %>
<%@ Import Namespace="System.Web.UI.WebControls.WebParts" %>
<script runat="server">
/*
 * upload demo for c# .net 2.0
 * 
 * @requires xhEditor
 * @author Jediwolf<jediwolf@gmail.com>
 * @licence LGPL(http://www.opensource.org/licenses/lgpl-license.php)
 * 
 * @Version: 0.1.3 (build 100504)
 * 
 * 注1：本程序仅为演示用，请您务必根据自己需求进行相应修改，或者重开发
 * 注2：本程序将HTML5上传与普通POST上传转换为byte类型统一处理
 */
    protected void Page_Load(object sender, EventArgs e) {
        Response.Charset = "UTF-8";

        // 初始化一大堆变量
        string  inputname = "filedata";//表单文件域name
        string  attachdir = "upload";     // 上传文件保存路径，结尾不要带/
        int     dirtype = 1;                 // 1:按天存入目录 2:按月存入目录 3:按扩展名存目录  建议使用按天存
        int     maxattachsize = 2097152;     // 最大上传大小，默认是2M
        string  upext = "txt,rar,zip,jpg,jpeg,gif,png,swf,wmv,avi,wma,mp3,mid";    // 上传扩展名
        int     msgtype = 2;                 //返回上传参数的格式：1，只返回url，2，返回参数数组
        string  immediate = Request.QueryString["immediate"];//立即上传模式，仅为演示用
        byte[]  file;                     // 统一转换为byte数组处理
        string  localname = "";
        string  disposition = Request.ServerVariables["HTTP_CONTENT_DISPOSITION"];
        string  err = "";
        string  msg = "''";

        if (disposition != null) {
            // HTML5上传
            file = Request.BinaryRead(Request.TotalBytes);
            localname = Regex.Match(disposition, "filename=\"(.+?)\"").Groups[1].Value;// 读取原始文件名
        } else {
            HttpFileCollection filecollection = Request.Files;
            HttpPostedFile postedfile = filecollection.Get(inputname);

            // 读取原始文件名
            localname = postedfile.FileName;
            // 初始化byte长度.
            file = new Byte[postedfile.ContentLength];

            // 转换为byte类型
            System.IO.Stream stream = postedfile.InputStream;
            stream.Read(file, 0, postedfile.ContentLength);
            stream.Close();

            filecollection = null;
        }

        if (file.Length == 0) err = "无数据提交";
        else {
            if (file.Length > maxattachsize) err = "文件大小超过" + maxattachsize + "字节";
            else {
                string attach_dir, attach_subdir, filename, extension, target;

                // 取上载文件后缀名
                extension = GetFileExt(localname);

                if (("," + upext + ",").IndexOf("," + extension + ",") < 0) err = "上传文件扩展名必需为：" + upext;
                else {
                    switch (dirtype) {
                        case 2:
                            attach_subdir = "month_" + DateTime.Now.ToString("yyMM");
                            break;
                        case 3:
                            attach_subdir = "ext_" + extension;
                            break;
                        default:
                            attach_subdir = "day_" + DateTime.Now.ToString("yyMMdd");
                            break;
                    }
                    attach_dir = attachdir + "/" + attach_subdir + "/";

                    // 生成随机文件名
                    Random random = new Random(DateTime.Now.Millisecond);
                    filename = DateTime.Now.ToString("yyyyMMddhhmmss") + random.Next(10000) + "." + extension;

                    target = attach_dir + filename;
                    try {
                        CreateFolder(Server.MapPath(attach_dir));

                        System.IO.FileStream fs = new System.IO.FileStream(Server.MapPath(target), System.IO.FileMode.Create, System.IO.FileAccess.Write);
                        fs.Write(file, 0, file.Length);
                        fs.Flush();
                        fs.Close();
                    } catch (Exception ex) {
                        err = ex.Message.ToString();
                    }

                    // 立即模式判断
                    if (immediate == "1") target = "!" + target;
                    target = jsonString(target);
                    if (msgtype == 1) msg = "'" + target + "'";
                    else msg = "{'url':'" + target + "','localname':'" + jsonString(localname) + "','id':'1'}";
                }
            }
        }
        file = null;
        Response.Write("{'err':'" + jsonString(err) + "','msg':" + msg + "}");
    }
    string jsonString(string str) {
        str = str.Replace("\\", "\\\\");
        str = str.Replace("/", "\\/");
        str = str.Replace("'", "\\'");
        return str;
    }
    string GetFileExt(string FullPath) {
        if (FullPath != "") return FullPath.Substring(FullPath.LastIndexOf('.') + 1).ToLower();
        else return "";
    }
    void CreateFolder(string FolderPath) {
        if (!System.IO.Directory.Exists(FolderPath)) System.IO.Directory.CreateDirectory(FolderPath);
    }
</script>