【1】ASP.NET异步（1）

<form id="form1" runat="server">
        <asp:ScriptManager ID="ScriptManager1" runat="server">
        </asp:ScriptManager>
        <div>
            时间1：<asp:Label ID="Label1" runat="server"></asp:Label>
            <br />
            <br />
            <fieldset style="width: 300px; height: 60px">
                <legend>局部更新</legend>
                <asp:UpdatePanel ID="UpdatePanel1" runat="server">
                    <ContentTemplate>
                        时间2：<asp:Label ID="Label2" runat="server"></asp:Label>
                    </ContentTemplate>
                    <Triggers>
                        <asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click" />
                    </Triggers>
                </asp:UpdatePanel>
            </fieldset>
            <br />
            <br />
            <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="显示时间" Width="55px" />
        </div>
    </form>