1         private void button1_Click(object sender, EventArgs e) 2         { 3             //FileStream可以读写任何文件，SteamReader、SteamWriter只适合读写文本文件 4  5             using (FileStream fs = new FileStream("test.txt", FileMode.OpenOrCreate, FileAccess.Read)) 6             { 7                 byte[] buffer = new byte[1024 * 1024];//Filestream读取、写入时需要以字节数组形式。 8                 string ct = ""; 9                 while (true)//大的文件需要分几次读取，所以需要循环读取10                 {11                     int a = fs.Read(buffer, 0, buffer.Length);12                     13                     ct += Encoding.Unicode.GetString(buffer);14                     if (a == 0)15                     {16                         break;17                     }18                 }19                 textBox1.Text = ct;20             }21 22 23         }24 25         private void button2_Click(object sender, EventArgs e)26         {27             28             //把文件test.pdf复制为test1.pdf29             using (FileStream fsread = new FileStream("test.pdf", FileMode.OpenOrCreate, FileAccess.Read))30             {31                 using (FileStream fswriter = new FileStream("test1.pdf", FileMode.Create, FileAccess.Write))32                 {33                     byte[] bytes = new byte[1024 * 1024];34                     while (true)35                     {36                         int a = fsread.Read(bytes, 0, bytes.Length);37                         fswriter.Write(bytes, 0, a);38                         if(a==0)39                         {40                         break ;41                         }42                     }43                 }44             }45             MessageBox.Show("复制成功");46         }47 48         private void button_sr_Click(object sender, EventArgs e)49         {50             string readers = "";51             using (StreamReader sr = new StreamReader("test.txt", Encoding.Default))52             {53                 char [] buffer=new char [2014*2014];//准备一个char数组作为容器54                 while (true )//当文本太多，一次没有读完，一直读取55                 {56                     int a = sr.Read(buffer, 0, buffer.Length);57                     if(a==0)58                     {break ;}59                     readers += new string(buffer);//重新把char数组转换成文本60                 }61                 62             }63             textBox1.Text = readers;64         }65 66         private void button_sw_Click(object sender, EventArgs e)67         {68             using (StreamReader sr=new StreamReader ("test.txt",Encoding .Default) )69             {70             using (StreamWriter sw=new StreamWriter ("test2.txt",false ,Encoding .Default))71             {72                 73                 while (sr.Peek ()>=0)//用些方法判断是否读到了文件尾，不过好像会丢失空文本。74                 {75                    string a=  sr.ReadLine();76 77                    sw.WriteLine(a);78                 }79                 80             }81 82             }83         }