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. Downloaded Upload 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
{
/// <summary>
/// UpFile 的摘要说明。
/// </summary>
public class UpFile
{
public UpFile()
{
}#region 是否允许该扩展名上传IsAllowedExtension
///<summary>
///是否允许该扩展名上传
///</summary>
///<paramname = "hifile">HtmlInputFile控件</param>
///<returns>允许则返回true,否则返回false</returns>
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<arrExtension.Length;i++)
{
if(strExtension.Equals(arrExtension[i]))
{
return true;
}
}
}
return false;
}
#endregion #region 判断上传文件大小是否超过最大值IsAllowedLength
/// <summary>
/// 判断上传文件大小是否超过最大值
/// </summary>
/// <param name="hifile">HtmlInputFile控件</param>
/// <returns>超过最大值返回false,否则返回true.</returns>
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
/// <summary>
/// 获取一个不重复的文件名
/// </summary>
/// <returns></returns>
public string GetUniqueString()
{
//得到的文件名形如：20050922101010
return DateTime.Now.ToString("yyyyMMddhhmmss");
}
#endregion #region 删除指定文件DeleteFile
/// <summary>
/// 删除指定文件
/// </summary>
/// <param name="strAbsolutePath">文件绝对路径</param>
/// <param name="strFileName">文件名</param>
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
/// <summary>
/// 上传文件并返回文件名
/// </summary>
/// <param name="hifile">HtmlInputFile控件</param>
/// <param name="strAbsolutePath">绝对路径.如:Server.MapPath(@"Image/upload")与Server.MapPath(@"Image/upload/")均可,用/符号亦可</param>
/// <returns>返回的文件名即上传后的文件名</returns>
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
/// <summary>
/// 重新上传文件，删除原有文件
/// </summary>
/// <param name="ffFile">HtmlInputFile控件</param>
/// <param name="strAbsolutePath">绝对路径.如:Server.MapPath(@"Image/upload")与Server.MapPath(@"Image/upload/")均可,用/符号亦可</param>
/// <param name="strOldFileName">旧文件名</param>
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:
<form id="form1" runat="server" method="post" enctype="multipart/form-data">
<input id="FileUpLoad" type="file" runat="server"/><br />
后台CS部分 按钮事件
//string strFileFullName = System.IO.Path.GetFileName(this.FileUpLoad.PostedFile.FileName);
//this.FileUpLoad.PostedFile.SaveAs(Server.MapPath("./xmlzip/") + strFileFullName);2. File download
----------
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 href=/"xmlzip/a.rar/">a.rar</a>"
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
///
/// Get the currently available file list
///
/// Whether a prompt message needs to pop up
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();
}
}
#endregionThe above is the detailed content of Example code for uploading and downloading files in ASP.NET. For more information, please follow other related articles on the PHP Chinese website!
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