检测AutoCompleteExtender选择事件

Question

既然控件没有这个事件，那么捕获AutoCompleteExtender select事件的最佳方法是什么？

这是我正在谈论的示例。我有两个带有链接的AutoCompleteExtender控件的文本框(Location1TextBox，Location2TextBox)。这部分运行得很好。现在的问题是，当用户从任何AutoCompleteExtender中进行选择时，我需要捕捉这个事件，并尝试计算location1和location2之间的距离。结果应该自动填充到DistanceTextBox中。有什么好的建议吗？我只希望它不会以文本框的onchange事件结束...

    <asp:UpdatePanel ID="UpdatePanel2" runat="server">
        <ContentTemplate>
            <asp:Label ID="TitleLabel" runat="server" Text='<% $resources:AppResource,LocationStart %>'
                CssClass="OneColumnLabel"></asp:Label>:<br />
            <asp:TextBox ID="Location1TextBox" runat="server" CssClass="TwoColumnMiddleLongText"
                ValidationGroup="Edit" AutoPostBack="true"></asp:TextBox>*
            <asp:RequiredFieldValidator ID="TitleRequiredFieldValidator" runat="server" ControlToValidate="Location1TextBox"
                Display="None" ErrorMessage='<% $resources:AppResource,LocationRequired %>' ValidationGroup="Edit"></asp:RequiredFieldValidator>
            <ajaxToolkit:AutoCompleteExtender runat="server" ID="AutoCompleteExtender1" TargetControlID="Location1TextBox"
                ServiceMethod="GetCompletionList" ServicePath="TravelOrder.aspx" MinimumPrefixLength="1"
                CompletionInterval="300" UseContextKey="True">
            </ajaxToolkit:AutoCompleteExtender>
            <asp:Label ID="Label7" runat="server" Text='<% $resources:AppResource,LocationArrival %>'
                CssClass="OneColumnLabel"></asp:Label>:<br />
            <asp:TextBox ID="Location2TextBox" runat="server" CssClass="TwoColumnMiddleLongText"
                ValidationGroup="Edit"></asp:TextBox>*
            <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ControlToValidate="Location2TextBox"
                Display="None" ErrorMessage='<% $resources:AppResource,LocationRequired %>' ValidationGroup="Edit"></asp:RequiredFieldValidator>
            <ajaxToolkit:AutoCompleteExtender runat="server" ID="AutoCompleteExtender2" TargetControlID="Location2TextBox"
                ServiceMethod="GetCompletionList" ServicePath="TravelOrder.aspx" MinimumPrefixLength="1"
                CompletionInterval="300" UseContextKey="True">
            </ajaxToolkit:AutoCompleteExtender>
            <asp:Label ID="Label8" runat="server" Text='<% $resources:AppResource,Distance %>'
                CssClass="OneColumnLabel"></asp:Label>:<br />
            <asp:TextBox ID="DistanceTextBox" runat="server" CssClass="OneColumnText" ValidationGroup="Edit"></asp:TextBox>*
            <asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ControlToValidate="DistanceTextBox"
                Display="None" ErrorMessage='<% $resources:AppResource,DistanceRequired %>' ValidationGroup="Edit"></asp:RequiredFieldValidator>
        </ContentTemplate>
    </asp:UpdatePanel>

Answer 1

您可以从目标文本框中删除AutoPostBack="true"，订阅TextChanged事件，并使用下面的函数作为itemSelected扩展器的客户端事件OnClientItemSelected="autoCompleteEx_ItemSelected"的处理程序

<script type="text/javascript">
     function autoCompleteEx_ItemSelected(sender, args) {
          __doPostBack(sender.get_element().name, "");
     }
</script>