title: Placeholder losing data after postback
body: <p>I'm reading a list of id numbers from a database table into a placeholder textbox but however; if I do a button click the data is removed. </p>
  
  <pre><code> protected void btnSearch_Click(object sender, EventArgs e)
      {
  
       while (myReader.Read())
          {
  
  
              TextBox txt = new TextBox();
              txt.Text = (string)myReader["idNumber"];
              txt.ID = "txt" + i;
              txt.ReadOnly = true;
              ContentPlaceHolder1.Controls.Add(txt);
              ContentPlaceHolder1.Controls.Add(new LiteralControl("&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;"));
  
              i++;
          }
  }
  </code></pre>