C # Processing of resumable upload and download files

Class for resumable upload and download of Files written in C #

This example uses C # upload and Servlet for receiving.

C # resumable download of files as clients and servlets as servers

There is debugging failed, mail me: lijiangchxp@sina.com.cn

Using system;
Using log4net;
Using system. collections;
Using system. text;
Using system. IO;
Using system. net;
Using log4net. config;
Using chxp. business;
Namespace chxp. Service
{
Public class filelib
{
# Region attributes
Private string filename = "";
Public String filename
{
Get {return filename ;}
Set {filename = value ;}
}

# Endregion

Private Static readonly ilog log = logmanager. getlogger (typeof (filelib ));

# Region File Upload

/// <Summary>
/// Upload a file (automatically split)
/// </Summary>
/// <Param name = "filepath"> full path name of the file to be uploaded (@ "E:/FTP/ftproot/20070228dqck.zip") </param>
/// <Param name = "hosturl"> server address </param>
/// <Param name = "bytecount"> split byte size </param>
/// <Param name = "userid"> host user id </param>
/// <Param name = "cruuent"> Current byte pointer </param>
/// <Returns> success returns ""; Failure Returns an error message </returns>
Public String uploadfile (string filepath, string hosturl, int bytecount, string userid, long cruuent)
{
String tmpurl = hosturl;
Bytecount = bytecount * 1024;
// Http: // localhost: 8080/fism/app? Metric & userid = Test & NPOs = 333
// Action = Length

System. net. WebClient webclientobj = new system. net. WebClient ();
Filestream fstream = new filestream (filepath, filemode. Open, fileaccess. Read );
Binaryreader breader = new binaryreader (fstream );
Long length = fstream. length;
String smsg = "the layout is uploaded successfully ";
String filename = filepath. substring (filepath. lastindexof ('//') + 1 );
Try
{

# Region resume processing
Byte [] data;
If (cruuent> 0)
{
Fstream. Seek (cruuent, seekorigin. Current );
}
# Endregion

# Region split File Upload
For (; cruuent <= length; cruuent = cruuent + bytecount)
{
If (cruuent + bytecount> length)
{
Data = new byte [convert. toint64 (length-cruuent)];
Breader. Read (data, 0, convert. toint32 (length-cruuent )));
}
Else
{
Data = new byte [bytecount];
Breader. Read (data, 0, bytecount );
}

Try
{
Log. debug (data );

//***
Hosturl = tmpurl + "& Action = upload" + "& filename =" + filename + "& userid =" + userid + "& NPOs =" + cruuent. tostring ();
Byte [] byremoteinfo = webclientobj. uploaddata (hosturl, "Post", data );
String sremoteinfo = system. Text. encoding. Default. getstring (byremoteinfo );

// Obtain the returned information
If (sremoteinfo. Trim ()! = "")
{
Smsg = sremoteinfo;
Break;

}
}
Catch (exception ex)
{
Smsg = ex. tostring ();
Break;
}
# Endregion

}
}
Catch (exception ex)
{
Smsg = smsg + ex. tostring ();
}
Try
{
Breader. Close ();
Fstream. Close ();
}
Catch (exception exmsg)
{
Smsg = exmsg. tostring ();
}

GC. Collect ();
Return smsg;
}
# Endregion

# Region get File Size
/// <Summary>
/// Obtain the size of the Remote Server File in bytes
/// </Summary>
/// <Param name = "filepath"> full path name of the file to be uploaded </param>
/// <Param name = "hosturl"> server address </param>
/// <Param name = "userid"> host user id </param>
/// <Returns> Remote File Size </returns>
Public long getremotefilelength (string filepath, string hosturl, string userid)
{
Long length = 0;
System. net. WebClient webclientobj = new system. net. WebClient ();

String filename = filepath. substring (filepath. lastindexof ('//') + 1 );

Hosturl = hosturl + "& Action = length" + "& filename =" + filename + "& userid =" + userid + "& NPOs = 0 ";

Byte [] DATA = new byte [0];
Byte [] byremoteinfo = webclientobj. uploaddata (hosturl, "Post", data );
String sremoteinfo = system. Text. encoding. Default. getstring (byremoteinfo); // The main system does not handle exceptions.
Try
{
Length = convert. toint64 (sremoteinfo );
}
Catch (exception Exx)
{
The length = convert. toint64 (sremoteinfo) Statement in log. Error ("filelib class getremotefilelength () is abnormal:" + Exx. Message); // We forcibly handle the exception
Length = 0;
}
GC. Collect ();

Return length;

}

/// <Summary>
/// Obtain the size of the local file in bytes
/// </Summary>
/// <Param name = "filepath"> full local file path </param>
/// <Returns> local file size in bytes </returns>
Public long getlocalfilelength (string filepath)
{
Long length = 0;
Try
{
String filename = filepath. substring (filepath. lastindexof ('//') + 1 );
Filestream S = new filestream (filepath, filemode. Open );
Length = S. length;
S. Close ();
}
Catch (exception ex)
{
Log. Error ("An error occurred while obtaining the local file size in the filelib class:" + ex. Message );
}
Return length;

}
# Endregion

# Region File Download
Public bool downloadfile (string localpath, string hosturl, int bytecount, string userid, long cruuent)
{

Bool result = true;


String tmpurl = hosturl;

Bytecount = bytecount * 1024;
Hosturl = tmpurl + "& NPOs =" + cruuent. tostring ();

System. Io. filestream FS;
FS = new filestream (localpath, filemode. openorcreate );
If (cruuent> 0)
{
// Offset pointer
FS. Seek (cruuent, system. Io. seekorigin. Current );
}

System. net. httpwebrequest request = (system. net. httpwebrequest) system. net. httpwebrequest. Create (hosturl );
If (cruuent> 0)
{
Request. addrange (convert. toint32 (cruuent); // set the range value
}

Try
{
// Request from the server to obtain the Server Response Data Stream
System. Io. Stream NS = request. getresponse (). getresponsestream ();

Byte [] nbytes = new byte [bytecount];
Int nreadsize = 0;
Nreadsize = NS. Read (nbytes, 0, bytecount );

While (nreadsize> 0)
{
FS. Write (nbytes, 0, nreadsize );
Nreadsize = NS. Read (nbytes, 0, bytecount );

}
FS. Close ();
NS. Close ();
}
Catch (exception ex)
{
Log. Error ("Download" + localpath + "failed! "+" Cause: "+ ex. Message );
FS. Close ();
Result = false;
}

Return result;

}
# Endregion

}
}

 

This article from the csdn blog, reproduced please indicate the source: http://blog.csdn.net/lijiangchxp2005/archive/2008/04/22/2315105.aspx