C#文件分割的方法

本文实例讲述了c#文件分割的方法。分享给大家供大家参考。具体如下：

1. 小文件分割（适用于小于等于64m的文件）：

using system;
using system.io;
string filetosplit=@"c:\temp\data.bin";
string targetpath=@"d:\store";
filestream fsr = new filestream(filetosplit, filemode.open, fileaccess.read);
long filelength=fsr.length;
byte[] btarr = new byte[filelength];
fsr.read(btarr, 0, (int)filelength);
fsr.close();
int splitcount=3;
long partlength=filelength/splitcount+filelength%splitcount;
int ncount=(int)math.ceiling((double)filelength/partlength);
string strfilename=path.getfilename(filetosplit);
long bytecount=0;
for(int i=1;i<=ncount;i++,bytecount=(i<ncount?bytecount+partlength:filelength-partlength))
{
  filestream fsw = new filestream(targetpath + path.directoryseparatorchar+ strfilename +i, filemode.create, fileaccess.write);
  fsw.write(btarr, (int)bytecount, (int)(i<ncount?partlength:filelength-bytecount));
  fsw.flush();
  fsw.close();
}

2. 大文件分割（适用于大于64m的文件）

using system;
using system.io
string filetosplit=@"c:\temp\data.bin";
string targetpath=@"d:\store";
filestream fsr = new filestream(filetosplit, filemode.open, fileaccess.read);
long filelength=fsr.length;
byte[] btarr = new byte[filelength];
fsr.read(btarr, 0, (int)filelength);
fsr.close();
int splitcount=3;
long partlength=filelength/splitcount+filelength%splitcount;
int ncount=(int)math.ceiling((double)filelength/partlength);
string strfilename=path.getfilename(filetosplit);
long bytecount=0;
for(int i=1;i<=ncount;i++,bytecount=(i<ncount?bytecount+partlength:filelength-partlength))
{
  filestream fsw = new filestream(targetpath + path.directoryseparatorchar+ strfilename +i, filemode.create, fileaccess.write);
  long bc=bytecount;
  long partcount=i<ncount?partlength:filelength-bc;
  int partbuffercount=(int)(partcount<int.maxvalue/32?partcount:int.maxvalue/32);
  int nc=(int)math.ceiling((double)partcount/partbuffercount);
  for(int j=1;j<=nc;j++,bc=(j<ncount?bc+partbuffercount:partcount-partbuffercount))
    fsw.write(btarr, (int)bc, (int)(j<nc?partbuffercount:partcount-bc));
  fsw.flush();
  fsw.close();
}
fsr.close();

希望本文所述对大家的c#程序设计有所帮助。