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浅谈ASP.NET文件下载函数使用方法

  【IT168 技术文档】ASP.NET文件下载函数使用是什么情况呢?在你的Page_Load中添加这样的代码:

   Page.Response.Clear();
  
bool success = ResponseFile(Page.Request, Page.Response, "目的文件名称", @"源文件路径", 1024000);
  
if (!success) Response.Write("下载文件出错!"); Page.Response.End();
  ASP.NET文件下载函数代码为:
  
public static bool ResponseFile(HttpRequest _Request,HttpResponse _Response,string _fileName,string _fullPath, long _speed) {
  
try
  {
  FileStream myFile
= new FileStream(_fullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite);
  BinaryReader br
= new BinaryReader(myFile);
  
try
  {
  _Response.AddHeader(
"Accept-Ranges", "bytes"
  );
  _Response.Buffer
= false;
  
long fileLength = myFile.Length;
  
long startBytes = 0; double pack = 10240;
  
//10K bytes
  
//int sleep = 200;
  
//每秒5次 即5*10K bytes每秒 int sleep = (int)Math.Floor(1000 * pack / _speed) + 1;
  if (_Request.Headers["Range"] != null)
  {
  _Response.StatusCode
= 206;
  
string[] range = _Request.Headers["Range"].Split(new char[] {'=', '-'});
  startBytes
= Convert.ToInt64(range[1]);
  }
  _Response.AddHeader(
"Content-Length", (fileLength - startBytes).ToString());
  
if (startBytes != 0) {
  
//Response.AddHeader("Content-Range", string.Format(" bytes {0}-{1}/{2}", startBytes, fileLength-1, fileLength));
  }
  _Response.AddHeader(
"Connection", "Keep-Alive");
  _Response.ContentType
= "application/octet-stream";
  _Response.AddHeader(
"Content-Disposition","attachment; filename=" + HttpUtility.UrlEncode(_fileName,System.Text.Encoding.UTF8) ); br.BaseStream.Seek(startBytes, SeekOrigin.Begin);
  
int maxCount = (int) Math.Floor((fileLength - startBytes) / pack) + 1;
  
for (int i = 0; i < maxCount; i++) { if (_Response.IsClientConnected) { _Response.BinaryWrite(br.ReadBytes(int.Parse(pack.ToString()))); Thread.Sleep(sleep);
  }
else { i=maxCount;
  }
  } }
  
catch
  {
  
return false;
  }
  
finally
  {
  br.Close();
  myFile.Close();
  }
  }
  
catch
  {
  
return false;
  }
  
return true;
  }

 

  这样就实现了文件下载时,不管是什么格式的文件,都能够弹出打开/保存窗口.

  ASP.NET文件下载函数的基本情况就向你介绍到这里,希望对你了解ASP.NET文件下载函数有所帮助。

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