Asp.Net的FileUpload类实现上传文件实例

本文实例讲述了asp.net的fileupload类实现上传文件的方法。分享给大家供大家参考。

具体功能代码如下：

using system;
using system.collections.generic;
using system.text;
using system.web.ui;
using system.web;
using system.web.ui.webcontrols;
using system.collections;
using system.drawing;
using system.drawing.imaging;
using system.io;

namespace csframework.bll
{
   /// <summary>
   /// 支持上传的文件类型
   /// </summary>
   public enum uploadfiletype
   {
      articleattachment = 1,
      image = 2,
      video = 3,
      all = 4
   }
  
   /// <summary>
   /// 上传文件管理类
   /// </summary>
   public class cfileupload
   {
      private fileupload _fileupload;
      private string _savepath;
      private string _lastuploadedfile = string.empty;
      private bool _autogenfilename = false;
      private bool _autogenwatermark = false;
      public string lastuploadedfile { get { return _lastuploadedfile; } }
      private string _error = "";
     
      private string picture_file = "[.gif.png.jpeg.jpg]";
      private string zip_file = "[.zip.rar]";
      private string muilt_media_file = "[.mpeg.mpg.fla.wma]";
     
      private int img_max_width = 700;//指定宽度
      private int img_max_height = 0;//未指定高度
      private int max_size_upload = 1024;//最大支持上传小于1mb的文件。
     
      /// <summary>
      /// 构造器
      /// </summary>
      /// <param name="fileupload">asp.net fileupload对象</param>
      /// <param name="savepath">保存目录，不包含文件名</param>
      /// <param name="autogenfilename">自动生成文件名</param>
      public cfileupload(fileupload fileupload, string savepath, bool autogenfilename, bool autogenwatermark)
      {
         _savepath = savepath;
         _fileupload = fileupload;
         _autogenfilename = autogenfilename;
         _autogenwatermark = autogenwatermark;
      }
     
      /// <summary>
      /// 构造器
      /// </summary>
      /// <param name="fileupload">asp.net fileupload对象</param>
      /// <param name="savepath">保存目录，不包含文件名</param>
      public cfileupload(fileupload fileupload, string savepath)
      {
         _savepath = savepath;
         _fileupload = fileupload;
      }
     
      /// <summary>
      /// 上传rar文件
      /// </summary>
      public bool uploadrarfile()
      {
         return doupload(zip_file);
      }
     
      /// <summary>
      /// 上传视频文件
      /// </summary>
      public bool uploadvideo()
      {
         return doupload(muilt_media_file);
      }
     
      /// <summary>
      /// 上传图片文件
      /// </summary>
      public bool uploadimage()
      {
         return doupload(picture_file);
      }
     
      public bool uploadimage(int maxwidth, int maxheight)
      {
         this.img_max_width = maxwidth;
         this.img_max_height = maxheight;
         return doupload(picture_file);
      }
     
      /// <summary>
      /// 上传任何支持的文件
      /// </summary>
      public bool uploadanysupported()
      {
         return doupload(picture_file zip_file muilt_media_file);
      }
     
      /// <summary>
      /// 生成新的文件名
      /// </summary>
      private string getnewfilename(string folder, string filename)
      {
         if (_autogenfilename) //自动生成32位guid文件名
         {
            string ext = system.io.path.getextension(filename);
            string newfile = guid.newguid().tostring().replace("-", "") ext;
            return folder newfile;
         }
         else
         {
            if (system.io.file.exists(folder filename))
            {
               string ext = system.io.path.getextension(filename);
               string filebody = filename.replace(ext, "");
              
               int x = 1;
               while (true) //如果文件存在，生成尾部带(x)的文件
               {
                  string newfile = folder filebody "(" x.tostring() ")" ext;
                  if (!system.io.file.exists(newfile))
                  return folder filebody "(" x.tostring() ")" ext;
                  else
                  x ;
               }
            }
            else
            return folder filename;
         }
      }
     
      /// <summary>
      /// 最大支持小于1mb的文件。
      /// </summary>
      private bool allowmaxsize(int filelength)
      {
         double kb = filelength / 1024;
         return (int)kb < max_size_upload;
      }
     
      private bool doupload(string allowedextensions)
      {
         try
         {
            bool fileok = false;
           
            if (!_fileupload.hasfile) throw new exception("没有文件！"); //上传控件中如果不包含文件，退出
           
            // 得到文件的后缀
            string fileextension = system.io.path.getextension(_fileupload.filename).tolower();
           
            // 看包含的文件是否是被允许的文件后缀
            fileok = allowedextensions.indexof(fileextension) > 0;
            if (!fileok) throw new exception("不支持的文件格式！");
           
            //检查上传文件大小
            fileok = allowmaxsize(_fileupload.filebytes.length);
            if (!fileok) throw new exception("图片文件不能大于" max_size_upload.tostring() "kb！");
           
            try
            {
               // 文件另存在服务器指定目录下
               string savefile = getnewfilename(_savepath, _fileupload.filename);
              
               if (isuploadimage(fileextension))//保存图片
               {
                  system.drawing.image output = cimagelibrary.frombytes(_fileupload.filebytes);
                 
                  // 检查图片宽度/高度/大小
                  if (this.img_max_width != 0 && output.width > this.img_max_width)
                  {
                     output = cimagelibrary.getoutputsizeimage(output, this.img_max_width);
                  }
                 
                  bitmap bmp = new bitmap(output);
                 
                  this.createdir(path.getdirectoryname(savefile));
                 
                  bmp.save(savefile, output.rawformat);
                  bmp.dispose();
                  output.dispose();
                 
                  if (_autogenwatermark)
                  {
                     watermarkimage genwatermark = new watermarkimage();
                     genwatermark.drawwords(savefile, appconfig.current.watermarkmain,
                     appconfig.current.watermarkdesc, float.parse("0.2"));
                  }
               }
               else//其它任何文件
               {
                  this.createdir(path.getdirectoryname(savefile));
                 
                  _fileupload.postedfile.saveas(savefile);
               }
              
               _lastuploadedfile = savefile;
              
               return true;
            }
            catch (exception ex)
            {
               throw new exception("上传文件时发生未知错误！" ex.message);
            }
         }
         catch (exception ex)
         {
            _error = ex.message;
            return false;
         }
      }
     
      private void createdir(string dir)
      {
         if (directory.exists(dir) == false)
         directory.createdirectory(dir);
      }
     
      private bool isuploadimage(string fileextension)
      {
         bool isimage = picture_file.indexof(fileextension) > 0;
         return isimage;
      }
   }
}

希望本文所述对大家的asp.net程序设计有所帮助。