操作文件系统（2）二进制文件的建、写、读

private void Button3_Click(object sender, System.EventArgs e)

{

//写二进制文件

BinaryWriter bw;

//创建一个二进制文件

FileStream fs=new FileStream (MapPath("mydata.data"),FileMode.Create );

bw=new BinaryWriter (fs);//初始化一个BinaryWriter

for(int i=0;i<200;i++)

bw.Write (i);//写入

bw.Close ();//关闭

}

private void Button4_Click(object sender, System.EventArgs e)

{

//读二进制文件

BinaryReader br;

string str="";

FileStream fs=new FileStream (MapPath("mydata.data"),FileMode.Open );

br=new BinaryReader (fs);

for(int i=0;i<fs.Length /4;i++)

str+=br.ReadInt32 ().ToString ();

TextBox1.Text =str;

}