using System.IO;
//Check that the uploaded file is not empty
if(File1.PostedFile!=null) { string nam = File1.PostedFile.FileName ; //取得文件名(抱括路径)里最后一个"."的索引 int i= nam.LastIndexOf("."); //取得文件扩展名 string newext =nam.Substring(i); //这里我自动根据日期和文件大小不同为文件命名,确保文件名不重复 DateTime now = DateTime.Now; string newname=now.DayOfYear.ToString()+File1.PostedFile.ContentLength.ToString(); //保存文件到你所要的目录,这里是IIS根目录下的upload目录.你可以改变. //注意: 我这里用Server.MapPath()取当前文件的绝对目录.在asp.net里""必须用""代替 File1.PostedFile.SaveAs(Server.MapPath("upload"+newname+newext)); this.HyperLink1.NavigateUrl ="upload"+newname+newext; //得到这个文件的相关属性:文件名,文件类型,文件大小 //fname.Text=File1.PostedFile.FileName; //fenc.Text=File1.PostedFile.ContentType ; //fsize.Text=File1.PostedFile.ContentLength.ToString(); }
You can use File in the HTML control in .net to upload Field's upload control, after you drag it to the form, you can right-click to use it as a server-side control. Just write a few lines of code you want to upload. Download directly and connect to the file you want to download. DownloadedUpload the file to the server, directly add a hyperlink and download. The following are the classes used to upload files:
Description: You can use it by directly copying and pasting in the cs file. using System;
using System.IO;
using System.Web.UI.HtmlControls;namespace youjian { /// /// UpFile 的摘要说明。 /// public class UpFile { public UpFile() { }#region 是否允许该扩展名上传IsAllowedExtension /// ///是否允许该扩展名上传 /// ///HtmlInputFile控件 ///允许则返回true,否则返回false public bool IsAllowedExtension(HtmlInputFile hifile) { string strOldFilePath = ""; string strExtension = ""; //允许上传的扩展名，可以改成从配置文件中读出 string[]arrExtension = {".gif",".jpg",".jpeg",".bmp",".png"}; if(hifile.PostedFile.FileName != string.Empty) { strOldFilePath = hifile.PostedFile.FileName; //取得上传文件的扩展名 strExtension = strOldFilePath.Substring(strOldFilePath.LastIndexOf(".")); //判断该扩展名是否合法 for(int i = 0;i /// 判断上传文件大小是否超过最大值 /// /// HtmlInputFile控件 /// 超过最大值返回false,否则返回true. public bool IsAllowedLength(HtmlInputFile hifile) { //允许上传文件大小的最大值,可以保存在xml文件中,单位为KB int i = 20; //如果上传文件的大小超过最大值,返回flase,否则返回true. if(hifile.PostedFile.ContentLength > i * 1024) { return false; } return true; } #endregion #region 获取一个不重复的文件名GetUniqueString /// /// 获取一个不重复的文件名 /// /// /// 删除指定文件 /// /// 文件绝对路径 /// 文件名 public void DeleteFile(string strAbsolutePath, string strFileName) { //判断路径最后有没有/符号，没有则自动加上 if(strAbsolutePath.LastIndexOf("//") == strAbsolutePath.Length) { //判断要删除的文件是否存在 if(File.Exists(strAbsolutePath + strFileName)) { //删除文件 File.Delete(strAbsolutePath + strFileName); } } else { if(File.Exists(strAbsolutePath + "//" + strFileName)) { File.Delete(strAbsolutePath + "//" + strFileName); } } } #endregion #region 上传文件并返回文件名 SaveFile /// /// 上传文件并返回文件名 /// /// HtmlInputFile控件 /// 绝对路径.如:Server.MapPath(@"Image/upload")与Server.MapPath(@"Image/upload/")均可,用/符号亦可 /// 返回的文件名即上传后的文件名 public string SaveFile(HtmlInputFile hifile,string strAbsolutePath) { string strOldFilePath = "",strExtension = "",strNewFileName = ""; //如果上传文件的文件名不为空 if(hifile.PostedFile.FileName != string.Empty) { strOldFilePath = hifile.PostedFile.FileName; //取得上传文件的扩展名 strExtension = strOldFilePath.Substring(strOldFilePath.LastIndexOf(".")); //文件上传后的命名 strNewFileName = GetUniqueString() + strExtension; //如果路径末尾为/符号，则直接上传文件 if(strAbsolutePath.LastIndexOf("//") == strAbsolutePath.Length) { hifile.PostedFile.SaveAs(strAbsolutePath + strNewFileName); } else { hifile.PostedFile.SaveAs(strAbsolutePath + "//" + strNewFileName); } } return strNewFileName; } #endregion #region 重新上传文件，删除原有文件CoverFile /// /// 重新上传文件，删除原有文件 /// /// HtmlInputFile控件 /// 绝对路径.如:Server.MapPath(@"Image/upload")与Server.MapPath(@"Image/upload/")均可,用/符号亦可 /// 旧文件名 public void CoverFile(HtmlInputFile ffFile,string strAbsolutePath,string strOldFileName) { //获得新文件名 string strNewFileName = GetUniqueString(); if(ffFile.PostedFile.FileName != string.Empty) { //旧图片不为空时先删除旧图片 if(strOldFileName != string.Empty) { DeleteFile(strAbsolutePath,strOldFileName); } SaveFile(ffFile,strAbsolutePath); } } #endregion
1. File upload
-------- --
The following points:
HTML part:
2. File download
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ListBox的SelectedIndexChanged事件 设定相关下载连接 protected void lst_DownLoadFileList_SelectedIndexChanged(object sender, EventArgs e) { try { string strJS = "window.open('xmlzip/"; strJS += this.lst_DownLoadFileList.SelectedItem.Text.Trim(); strJS += "'); return false; "; this.imgbtn_DownLoadFile.Attributes.Add("onclick", strJS); } catch (Exception ex) { ex.ToString(); } }
Or you can also change the Text value of Label to achieve a super link for file download after clicking
this.Label1.Text = "a.rar"
3. File deletion
---------
string strFilePath = Server.MapPath("../CountryFlowMgr/xmlzip/"+this.lst_DownLoadFileList.SelectedItem.Text.Trim()); if (File.Exists(strFilePath)) { File.Delete(strFilePath); if (File.Exists(strFilePath)) { Response.Write("ok"); } else { Response.Write("ok"); } }
4. Get the file list under the folder
-----------
#region Get the currently available file list
///
private void fn_getCurrFileList(bool IsAlert) { try { //查找xmlzip文件夹下 属于其本身UnitCoding的相关zip文件 string strXmlZipDirectory = Server.MapPath("../xmlzip/"); if (Directory.Exists(strXmlZipDirectory)) { //DirectoryInfo di = new DirectoryInfo(Environment.CurrentDirectory); DirectoryInfo di = new DirectoryInfo(strXmlZipDirectory); FileInfo[] FI = di.GetFiles("*.zip");//只查.zip文件 if (FI.Length > 0) { lst_DownLoadFileList.Items.Clear(); foreach (FileInfo tmpFI in FI) { ListItem tmpItem = new ListItem(); tmpItem.Text = tmpFI.Name; lst_DownLoadFileList.Items.Add(tmpItem); } lst_DownLoadFileList.SelectedIndex = 0; } else { if (IsAlert) { Response.write("查无可以下载的文件!"); } } } } catch (Exception ex) { ex.ToString(); } } #endregion
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