C#的文件读写操作--流方式一次读写文件

Stream流读写文件： 
 
private void button3_Click(object sender, EventArgs e)
        {
            //将textBox3.Text写入nihao.txt文件
            Stream s = new FileStream("nihao.txt",FileMode.Create,FileAccess.Write);
//打开模式，访问方式
            StreamWriter sw = new StreamWriter(s, Encoding.Default);//创建Stream流，指定编码方式
            sw.Write(textBox3.Text);
            sw.Close();
        }
 
private void button2_Click(object sender, EventArgs e)
        {
            //将nihao.txt文件读出到textBox3.Text
            Stream s = new FileStream("nihao.txt", FileMode.Open);
            StreamReader sr = new StreamReader(s,Encoding.Default);
            textBox3.Text= sr.ReadToEnd().ToString();
            sr.Close();
            s.Close();
            //sr.BaseStream的Position或Seek()可移动文件流指针到的任意位置。
          
        }
 
 
二进制文件的读写：
 
 private void button5_Click(object sender, EventArgs e)
        {
            Stream s = new FileStream("nihao1.txt", FileMode.Create);
            BinaryWriter sw = new BinaryWriter(s, Encoding.Unicode);
            sw.Write(textBox3.Text);
            sw.Close();
        }
        private void button6_Click(object sender, EventArgs e)
        {
           // MessageBox.Show(Convert.ToChar(97).ToString());
            Stream s = new FileStream("nihao1.txt", FileMode.Open);
            BinaryReader sr = new BinaryReader(s, Encoding.Unicode);
            textBox3.Text=sr.ReadString().ToString();
           
            sr.Close();
            s.Close();
        }