① asp.net中如何写下载代码
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text;
using System.IO;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
DownloadClass dd = new DownloadClass();
dd.StrUrl = "http://127.0.0.1/UI.rar";
dd.StrFileName="C:\\1.rar";
dd.DownloadFile();
Response.Write(dd.strError);
}
//测试用线程1断点续传下载网络上的文件到本地电脑
public class DownloadClass
{
public string StrUrl;//文件下载网址
public string StrFileName;//下载文件保存地址
public string strError;//返回结果
public long lStartPos = 0; //返回上次下载字节
public long lCurrentPos = 0;//返回当前下载字节
public long lDownloadFile;//返回当前下载文件长度
public void DownloadFile()
{
System.IO.FileStream fs;
if (System.IO.File.Exists(StrFileName))
{
fs = System.IO.File.OpenWrite(StrFileName);
lStartPos = fs.Length;
fs.Seek(lStartPos, System.IO.SeekOrigin.Current);
//移动文件流中的当前指针
}
else
{
fs = new System.IO.FileStream(StrFileName, System.IO.FileMode.Create);
lStartPos = 0;
}
//打开网络连接
try
{
System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(StrUrl);
long length = request.GetResponse().ContentLength;
lDownloadFile = length;
if (lStartPos > 0)
request.AddRange((int)lStartPos); //设置Range值
//向服务器请求，获得服务器回应数据流
System.IO.Stream ns = request.GetResponse().GetResponseStream();
byte[] nbytes = new byte[512];
int nReadSize = 0;
nReadSize = ns.Read(nbytes, 0, 512);
while (nReadSize > 0)
{
fs.Write(nbytes, 0, nReadSize);
nReadSize = ns.Read(nbytes, 0, 512);
lCurrentPos = fs.Length;
}
fs.Close();
ns.Close();
strError = "下载完成";
}
catch (Exception ex)
{
fs.Close();
strError = "下载过程中出现错误:" + ex.ToString();
}
}
}
}
② ASP 如何实现文件下载
你把要下载的文件名传到下载页面，用request("fileNameField")获取文件名
下面这地方改一下
iConcStr = "Provider=Microsoft.Jet.OLEDB.4.0;Persist Security Info=False" & _
";Data Source=" & server.mappath(request("fileNameField"))
点击回下载答的地方用<a href='下载页面路径?fileNameField=要下载的文件名'>下载文件</a>
这个
③ 如何用ASP实现文件下载
调用
response.Write("<a href=down.asp?filename="&UpLoadPath&ls_array(i+1)&">"&ls_array
(i)&"</td></tr>")
down.asp文件内容如下：
<%
Const FilePath = "UploadFile/" '文件存放路径
From_url = Cstr(Request.ServerVariables("HTTP_REFERER"))
Serv_url = Cstr(Request.ServerVariables("SERVER_NAME"))
Function GetFileName(longname)'/folder1/folder2/file.asp=>file.asp
while instr(longname,"/")
longname = right(longname,len(longname)-1)
wend
GetFileName = longname
End Function
Dim Stream
Dim Contents
Dim FileName
Dim TrueFileName
Dim FileExt
Const adTypeBinary = 1
FileName = Request.QueryString("FileName")
if FileName = "" Then
Response.Write "无效文件名！"
Response.End
End if
FileExt = Mid(FileName, InStrRev(FileName, ".") + 1)
Response.Clear
if lcase(right(FileName,3))="gif" or lcase(right(FileName,3))="jpg" or lcase(right(FileName,3))="png" then
Response.ContentType = "image/*" '对图像文件不出现下载对话框
else
Response.ContentType = "application/ms-download"
end if
Response.AddHeader "content-disposition", "attachment; filename=" & GetFileName(Request.QueryString("FileName"))
Set Stream = server.CreateObject("ADODB.Stream")
Stream.Type = adTypeBinary
Stream.Open
TrueFileName= FilePath &FileName
Response.Write TrueFileName
Response.End
Stream.LoadFromFile Server.MapPath(TrueFileName)
While Not Stream.EOS
Response.BinaryWrite Stream.Read(1024 * 64)
Wend
Stream.Close
Set Stream = Nothing
Response.Flush
Response.End
%>
④ 如何在asp.net中实现点击下载按钮进行文件下载
可以直接使用a标签的啊， href跟你文件所在的位置
⑤ asp.net 如何实现将服务器上的文件下载到本地
给你提供一点代码：
string fileURL = this.Server.MapPath("你要下载的文件路径");//文件路径，可用相对路径
FileInfo fileInfo = new FileInfo(fileURL);
Response.Clear();
Response.AddHeader("content-disposition", "attachment;filename=" +
Server.UrlEncode(fileInfo.Name.ToString()));//文件名
Response.AddHeader("content-length", fileInfo.Length.ToString());//文件大小
Response.ContentType = "application/octet-stream";
Response.ContentEncoding = System.Text.Encoding.Default;
Response.WriteFile(fileURL);
⑥ asp如何实现文件下载功能
CALL Response.Clear()//清除已经输出的内容
CALL Server.Transfer("aaa.exe")//重定向到文件
CALL Response.End()//结束其余代码执行