我有两个下拉列表，两个都带有 AutoPostBack="true"。第一个下拉列表有一个客户列表，第二个有一个员工列表。
截图：
当我在第一个下拉列表（在 fildset 1“Dados”上）选择一个项目时，fildset 2“Cliente”必须填充空白（如姓名、邮政编码、地址、电话号码等）。
但什么也没发生！有 OnSelectedIndexChange 事件和 AutoPostBack="true" 但没有任何效果。但是当我更改第二个下拉列表“Tecnico”时，第一个下拉列表着火了！
这是我的代码：
<asp:UpdatePanel ID="upGeral" runat="server">
<ContentTemplate>
<div >
<h1>Relatório de Atendimento</h1>
<br />
<div>
<fieldset style="width: 90%">
<legend>Dados</legend>
<table>
<tr>
<td>
<asp:Label Text="Cliente" runat="server" ID="lblCliente"></asp:Label>
</td>
<td colspan="3">
<asp:DropDownList ID="ddlClientes" runat="server" OnSelectedIndexChanged="ddlClientes_SelectedIndexChanged" AutoPostBack="true">
</asp:DropDownList>
<asp:Label ID="lblIdCliente" runat="server" Height="23px"></asp:Label>
</td>
<td>
<asp:UpdateProgress ID="UpdateProgress1" runat="server">
<ProgressTemplate>
<img src="../Imagens/Icones/ajax-loader.gif" alt="Loading..." />
</ProgressTemplate>
</asp:UpdateProgress>
</td>
</tr>
<tr>
<td>
<asp:Label runat="server" Text="Responsável" ID="lblResponsavel"></asp:Label>
</td>
<td>
<asp:TextBox runat="server" ID="txtResponsavel"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label runat="server" Text="Data Chegada" ID="lblDataChegada"></asp:Label>
</td>
<td>
<asp:TextBox runat="server" ID="txtDataChegada" onkeyup="formataData(event);" MaxLength="10"></asp:TextBox>
</td>
<td class="style3">
<asp:Label runat="server" Text="Hora Chegada" onkeyup="formataHora(event);" MaxLength="5"
ID="lblHoraChegada"></asp:Label>
</td>
<td class="style4">
<asp:TextBox runat="server" ID="txtHoraChegada" onkeyup="formataHora(event);" MaxLength="5"
Style="margin-left: 0px"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label runat="server" Text="Data Saída" ID="lblDataSaida"></asp:Label>
</td>
<td>
<asp:TextBox runat="server" ID="txtDataSaida" onkeyup="formataData(event);" MaxLength="10"></asp:TextBox>
</td>
<td class="style3">
<asp:Label runat="server" Text="Hora Saída" ID="lblHoraSaida"></asp:Label>
</td>
<td class="style4">
<asp:TextBox runat="server" ID="txtHoraSaida" onkeyup="formataHora(event);" MaxLength="5"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="lblKM" runat="server" Text="KM"></asp:Label>
</td>
<td>
<asp:TextBox ID="txtKM" runat="server" onkeyup="formataInteiro(event);"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:Label ID="lblTecnico" runat="server" Text="Técnico"></asp:Label>
</td>
<td>
<asp:DropDownList ID="ddlTecnico" runat="server" AutoPostBack="true">
</asp:DropDownList>
</td>
</tr>
</table>
</fieldset>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="ddlClientes" />
</Triggers>
</asp:UpdatePanel>
我不知道我能做些什么来修复它......有人可以帮助我吗？