public partial class ReaderInfo : Form
    {
        private CurrencyManager cmOrders;//数据导航

        public ReaderInfo()
        {
            InitializeComponent();
        }

        private void ReaderInfo_Load(object sender, EventArgs e)
        {
            sqlDataAdapter1.SelectCommand.Parameters[0].Value = "%%";
            sqlDataAdapter1.SelectCommand.Parameters[1].Value = "%%";
            sqlDataAdapter1.Fill(dataSet11);
            //绑定数据导航
            cmOrders = (CurrencyManager)BindingContext[dataSet11, "读者信息"];
            //为读者类型下拉列表框设置下拉列表
            string strConn = "workstation id=localhost;Integrated Security=SSPI;database=libbook";
            SqlConnection cn = new SqlConnection(strConn);
            cn.Open();
            SqlCommand cmd = cn.CreateCommand();
             = "select distinct 类型 from 读者类型";
            SqlDataReader dr = cmd.ExecuteReader();
            while (dr.Read())
            {
                cmb2.Items.Add(dr.GetValue(0).ToString().Trim());
            }
        }

        //----------根据输入的信息，查询读者信息--------
        private void button1_Click(object sender, EventArgs e)
        {
            sqlDataAdapter1.SelectCommand.Parameters[0].Value = "%%";
            sqlDataAdapter1.SelectCommand.Parameters[1].Value = "%%";
       
            if (txt1.Text != "")
            {
                sqlDataAdapter1.SelectCommand.Parameters[0].Value = "%" + txt1.Text + "%";
            }
            if (txt2.Text != "")
            {
                sqlDataAdapter1.SelectCommand.Parameters[1].Value = "%" + txt2.Text + "%";
            }
          
            dataSet11.读者信息.Clear();
            sqlDataAdapter1.Fill(dataSet11);
        }

}

我做一个图书管理系统的课设，想在打开读者信息界面时读入全部数据并显示出来，可以再根据读者编号或者读者姓名进行查询，但是就是打开读者信息界面时不能显示全部数据，在输入读者编号或者读者姓名后查询就可以显示。我不知道哪里错了，应该怎么改呀？