private void button1_Click(object sender, EventArgs e)
        {
            FileStream fs = new FileStream("e:\\wendati.12rj", FileMode.Create);
            BinaryWriter bw = new BinaryWriter(fs);
            string str = "1";
            while (str != " ")
            {

               str = Microsoft.VisualBasic.Interaction.InputBox("输入添加的数据", "添加", "90", -1, -1);
               richTextBox1.Text = richTextBox1 + str + "\n";
               al.Add(str);
               bw.Write(str);
               
            }