Asp.net 更改主下拉列表中的值时动态更改我的窗体下拉列表

我有一个下拉列表，从中选择值，当我从中选择值时，将显示一个表单。在该表格中，我有四个货币下拉列表，因此当我在下拉列表中选择.UK时，表格中的所有四个下拉列表都会显示英镑，当我选择.CA时，它会在表格中显示四个下拉列表中的CAN。我该怎么做

我的第一个下拉列表，从中选择要填写表单的值：

<asp:DropDownList ID="ddlPortal" runat="server" AutoPostBack="True" 
       onselectedindexchanged="ddlPortal_SelectedIndexChanged">
       <asp:ListItem>TRAVELONG</asp:ListItem>
       <asp:ListItem>ONETRAVEL</asp:ListItem>
       <asp:ListItem>.UK</asp:ListItem>
       <asp:ListItem>.CA-YYZ</asp:ListItem>
       <asp:ListItem>.CA-YVR</asp:ListItem>
   </asp:DropDownList>

<asp:ValidationSummary ID="vdm" runat="server" ForeColor="Red" />
<table class="style1">
       <tr>
           <td class="style13">
               <asp:Label ID="lblTid" runat="server" Text="TID"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbTid" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvTid" runat="server" 
                   ControlToValidate="tbTid" ErrorMessage="Enter Tid" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblUnusedTicketAmount" runat="server" 
                   Text="Unused Ticket Amount"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbUnusedTicketAmount" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvUnusedTicketAmount" runat="server" 
                   ControlToValidate="tbUnusedTicketAmount" ErrorMessage="Enter Amount" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:DropDownList ID="ddlUnusedAmount" runat="server" 
                   onselectedindexchanged="ddlUnusedAmount_SelectedIndexChanged">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style14">
               <asp:Label ID="lblPNR" runat="server" Text="PNR"></asp:Label>
           </td>
           <td class="style9">
               <asp:TextBox ID="tbPNR" runat="server"></asp:TextBox>
           </td>
           <td class="style8">
               <asp:RequiredFieldValidator ID="rfvPNR" runat="server" 
                   ControlToValidate="tbPNR" ErrorMessage="Enter PNR" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style9">
               <asp:Label ID="lblAirlinePenality" runat="server" Text="Airline Penality"></asp:Label>
           </td>
           <td class="style12">
               <asp:TextBox ID="tbAirlinePenality" runat="server"></asp:TextBox>
           </td>
           <td class="style10">
               <asp:RequiredFieldValidator ID="rfvAirlinePenality" runat="server" 
                   ControlToValidate="tbAirlinePenality" ErrorMessage="Enter Penality" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style10">
               <asp:DropDownList ID="ddlAirlinePenality" runat="server">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="lblTicketNumber" runat="server" Text="Ticket Number"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbTicketNumber" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvTicketNumber" runat="server" 
                   ControlToValidate="tbTicketNumber" ErrorMessage="Enter ESAC" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblNetRefundProcess" runat="server" Text="Net Refund Process"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbNetRefundProcess" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvNetRefundProcess" runat="server" 
                   ControlToValidate="tbNetRefundProcess" ErrorMessage="RequiredFieldValidator" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:DropDownList ID="ddlNetRefundProcess" runat="server">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="lblESACCode" runat="server" Text="ESAC Code"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbESACCode" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvESACCode" runat="server" 
                   ControlToValidate="tbESACCode" ErrorMessage="Enter ESAC code" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblRefundableCommision" runat="server" 
                   Text="Refundable Commission"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbRefundableCommision" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvRefundableCommission" runat="server" 
                   ControlToValidate="tbRefundableCommision" ErrorMessage="RequiredFieldValidator" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:DropDownList ID="ddlRefundableCommission" runat="server">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="lblWaiverCode" runat="server" Text="Waiver Code"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbWaiverCode" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvWaiverCode" runat="server" 
                   ControlToValidate="tbWaiverCode" ErrorMessage="Enter Waiver Code" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblCouponRefunded" runat="server" Text="Coupon Refunded"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbCouponRefund" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvCouponRefunded" runat="server" 
                   ControlToValidate="tbCouponRefund" ErrorMessage="Enter Coupon Refund" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               &nbsp;</td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="Label7" runat="server" Text="Remarks"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbRemarks" runat="server" TextMode="MultiLine"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvRemarks" runat="server" 
                   ControlToValidate="tbRemarks" ErrorMessage="Enter Remarks" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblRefundType" runat="server" Text="Refund Type"></asp:Label>
           </td>
           <td class="style11">
               <asp:DropDownList ID="ddlRefundType" runat="server">
                   <asp:ListItem>Full</asp:ListItem>
                   <asp:ListItem>Partial</asp:ListItem>
               </asp:DropDownList>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvRefundType" runat="server" 
                   ControlToValidate="ddlRefundType" ErrorMessage="Select Refund Type" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               &nbsp;</td>
       </tr>
       <tr>
           <td class="style13" colspan="7"> 
               &nbsp;<asp:Button ID="Button1" runat="server" onclick="Button1_Click" 
                   Text="Submit" />
           </td>
       </tr>
   </table>

TRAVELONG
单程
.英国
.CA-YYZ
.CA-YVR

需要更改的下拉列表：

<asp:DropDownList ID="ddlPortal" runat="server" AutoPostBack="True" 
       onselectedindexchanged="ddlPortal_SelectedIndexChanged">
       <asp:ListItem>TRAVELONG</asp:ListItem>
       <asp:ListItem>ONETRAVEL</asp:ListItem>
       <asp:ListItem>.UK</asp:ListItem>
       <asp:ListItem>.CA-YYZ</asp:ListItem>
       <asp:ListItem>.CA-YVR</asp:ListItem>
   </asp:DropDownList>

<asp:ValidationSummary ID="vdm" runat="server" ForeColor="Red" />
<table class="style1">
       <tr>
           <td class="style13">
               <asp:Label ID="lblTid" runat="server" Text="TID"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbTid" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvTid" runat="server" 
                   ControlToValidate="tbTid" ErrorMessage="Enter Tid" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblUnusedTicketAmount" runat="server" 
                   Text="Unused Ticket Amount"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbUnusedTicketAmount" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvUnusedTicketAmount" runat="server" 
                   ControlToValidate="tbUnusedTicketAmount" ErrorMessage="Enter Amount" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:DropDownList ID="ddlUnusedAmount" runat="server" 
                   onselectedindexchanged="ddlUnusedAmount_SelectedIndexChanged">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style14">
               <asp:Label ID="lblPNR" runat="server" Text="PNR"></asp:Label>
           </td>
           <td class="style9">
               <asp:TextBox ID="tbPNR" runat="server"></asp:TextBox>
           </td>
           <td class="style8">
               <asp:RequiredFieldValidator ID="rfvPNR" runat="server" 
                   ControlToValidate="tbPNR" ErrorMessage="Enter PNR" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style9">
               <asp:Label ID="lblAirlinePenality" runat="server" Text="Airline Penality"></asp:Label>
           </td>
           <td class="style12">
               <asp:TextBox ID="tbAirlinePenality" runat="server"></asp:TextBox>
           </td>
           <td class="style10">
               <asp:RequiredFieldValidator ID="rfvAirlinePenality" runat="server" 
                   ControlToValidate="tbAirlinePenality" ErrorMessage="Enter Penality" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style10">
               <asp:DropDownList ID="ddlAirlinePenality" runat="server">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="lblTicketNumber" runat="server" Text="Ticket Number"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbTicketNumber" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvTicketNumber" runat="server" 
                   ControlToValidate="tbTicketNumber" ErrorMessage="Enter ESAC" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblNetRefundProcess" runat="server" Text="Net Refund Process"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbNetRefundProcess" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvNetRefundProcess" runat="server" 
                   ControlToValidate="tbNetRefundProcess" ErrorMessage="RequiredFieldValidator" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:DropDownList ID="ddlNetRefundProcess" runat="server">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="lblESACCode" runat="server" Text="ESAC Code"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbESACCode" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvESACCode" runat="server" 
                   ControlToValidate="tbESACCode" ErrorMessage="Enter ESAC code" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblRefundableCommision" runat="server" 
                   Text="Refundable Commission"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbRefundableCommision" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvRefundableCommission" runat="server" 
                   ControlToValidate="tbRefundableCommision" ErrorMessage="RequiredFieldValidator" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               <asp:DropDownList ID="ddlRefundableCommission" runat="server">
                   <asp:ListItem>USD</asp:ListItem>
                   <asp:ListItem>CAD</asp:ListItem>
                   <asp:ListItem>GBP</asp:ListItem>
               </asp:DropDownList>
           </td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="lblWaiverCode" runat="server" Text="Waiver Code"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbWaiverCode" runat="server"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvWaiverCode" runat="server" 
                   ControlToValidate="tbWaiverCode" ErrorMessage="Enter Waiver Code" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblCouponRefunded" runat="server" Text="Coupon Refunded"></asp:Label>
           </td>
           <td class="style11">
               <asp:TextBox ID="tbCouponRefund" runat="server"></asp:TextBox>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvCouponRefunded" runat="server" 
                   ControlToValidate="tbCouponRefund" ErrorMessage="Enter Coupon Refund" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               &nbsp;</td>
       </tr>
       <tr>
           <td class="style13">
               <asp:Label ID="Label7" runat="server" Text="Remarks"></asp:Label>
           </td>
           <td class="style5">
               <asp:TextBox ID="tbRemarks" runat="server" TextMode="MultiLine"></asp:TextBox>
           </td>
           <td class="style4">
               <asp:RequiredFieldValidator ID="rfvRemarks" runat="server" 
                   ControlToValidate="tbRemarks" ErrorMessage="Enter Remarks" Font-Bold="True" 
                   ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td class="style5">
               <asp:Label ID="lblRefundType" runat="server" Text="Refund Type"></asp:Label>
           </td>
           <td class="style11">
               <asp:DropDownList ID="ddlRefundType" runat="server">
                   <asp:ListItem>Full</asp:ListItem>
                   <asp:ListItem>Partial</asp:ListItem>
               </asp:DropDownList>
           </td>
           <td>
               <asp:RequiredFieldValidator ID="rfvRefundType" runat="server" 
                   ControlToValidate="ddlRefundType" ErrorMessage="Select Refund Type" 
                   Font-Bold="True" ForeColor="Red">*</asp:RequiredFieldValidator>
           </td>
           <td>
               &nbsp;</td>
       </tr>
       <tr>
           <td class="style13" colspan="7"> 
               &nbsp;<asp:Button ID="Button1" runat="server" onclick="Button1_Click" 
                   Text="Submit" />
           </td>
       </tr>
   </table>

*
*
美元
计算机辅助设计
英镑
*
*
美元
计算机辅助设计
英镑
*
*
美元
计算机辅助设计
英镑
*
*
美元
计算机辅助设计
英镑
*
*
*
满满的
部分的
*

提前谢谢