C#读写txt文件的方法

1. 读取文件（StreamReader）

添加引用：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;

常用：

StreamReader sr = new StreamReader("TestFile.txt")

//StreamReader sr = new StreamReader("TestFile.txt",Encoding.GetEncoding("GB2312"))
//GBK
String line;
while ((line = sr.ReadLine()) != null)
{
   textBox1 .Text +=ii.ToString ()+" -"+line.ToString()+"\r\n";
}

2. 写入文件（StreamWriter）

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();