using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

 

 

byte[] byData = new byte[100];
char[] charData = new char[1000];

try
{
FileStream sFile = new FileStream("文件路径",FileMode.Open);
sFile.Seek(55, SeekOrigin.Begin);
sFile.Read(byData, 0, 100); //第一个参数是被传进来的字节数组,用以接受FileStream对象中的数据,第2个参数是字节数组中开始写入数据的位置,它通常是0,表示从数组的开端文件中向数组写数据,最后一个参数规定从文件读多少字符.
}
catch (IOException e)
{
Console.WriteLine("An IO exception has been thrown!");
Console.WriteLine(e.ToString());
Console.ReadLine();
return;
}
Decoder d = Encoding.UTF8.GetDecoder();
d.GetChars(byData, 0, byData.Length, charData, 0);
Console.WriteLine(charData);
Console.ReadLine();

 

 

FileStream fs = new FileStream(文件路径,FileMode.Create);
//获得字节数组

byte [] data =new UTF8Encoding().GetBytes(String);
//开始写入
fs.Write(data,0,data.Length);

//清空缓冲区、关闭流
fs.Flush();
fs.Close();

 

 

 

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;

 

 

StreamReader objReader = new StreamReader(文件路径);
      string sLine="";
      ArrayList LineList = new ArrayList();    
      while (sLine != null)
      {
        sLine = objReader.ReadLine();
        if (sLine != null&&!sLine.Equals(""))
          LineList.Add(sLine);
      }
            objReader.Close();
            return LineList;

 

 

  FileStream fs = new FileStream(文件路径, FileMode.Create);
StreamWriter sw = new StreamWriter(fs);
//开始写入
sw.Write(String);
 //清空缓冲区
sw.Flush();
//关闭流
sw.Close();
fs.Close();