隨手筆記

<div style="position: relative;">
     <asp:Label ID="LB_Tex" runat="server" Text="放行單號：" ForeColor="Blue" Font-Size="16pt" Font-Underline="True"></asp:Label>
      &nbsp;&nbsp;
      <span style="margin-left: 532px; width: 18px; overflow: hidden;">
          <asp:DropDownList ID="DDL_Rel" runat="server" Style="width: 260px; margin-left: -532px" Font-Size="17pt" AutoPostBack="True" OnSelectedIndexChanged="DDL_Rel_SelectedIndexChanged" >
          </asp:DropDownList>
      </span>
      <asp:TextBox ID="TB_Rel" runat="server" Style="width: 238px; position: absolute; left: 470px;" Font-Size="15.5pt" AutoPostBack="True" OnTextChanged="TB_Rel_TextChanged"></asp:TextBox>
      &nbsp;&nbsp;
      <asp:Button ID="Btn_Find" runat="server" cssClass="myButton" Text="Find" Font-Size="16pt" OnClick="Btn_Find_Click" />
      <asp:Button ID="Btn_Clear" runat="server" cssClass="myButton" Text="Clear" Font-Size="16pt" OnClick="Btn_Clear_Click" />
</div>

protected void DDL_Rel_SelectedIndexChanged(object sender, EventArgs e)
{
    TB_Rel.Text = DDL_Rel.SelectedItem.Text;
}
protected void TB_Rel_TextChanged(object sender, EventArgs e)
{
    try
    {
        DDL_Rel.SelectedValue = TB_Rel.Text;
    }
    catch
    {
        TB_Rel.Text = DDL_Rel.SelectedValue;
    }
}