我有一个带有三个 ajax 更新面板的 asp.net 页面。在每个面板中都有一些控件，每个 updatepanel 作为一个 ajax 更新进度控件。第一个更新面板有一个下拉列表，其中 autopostback = true。第二个和第三个更新面板将此下拉列表作为 asynpostback 触发器。当我在下拉列表中更改选择时，只出现第一个 updateprogress 加载图像，而其他不出现。
我该如何解决？
【问题讨论】：
尝试在更新面板中更改UpdateMode="Conditional"。
例子
<script type="text/javascript">
// Function to hide control on update
function onUpdateOfSubscribe() {
var panelProg = $get('divImage');
// set it to visible
panelProg.style.display = '';
// hide label if visible
var lbl = $get('<%= this.pnlRegister.ClientID %>');
lbl.innerHTML = '';
}
//Code to track the initiating event so to associate updateprogress
var currentPostBackElement;
function pageLoad() {
var manager = Sys.WebForms.PageRequestManager.getInstance();
manager.add_initializeRequest(OnInitializeRequest);
}
//On OnInitializeRequest
function OnInitializeRequest(sender, args) {
var manager = Sys.WebForms.PageRequestManager.getInstance();
currentPostBackElement = args.get_postBackElement().parentElement;
var cmdAuthoriseButton = '<%= btnRegister.ClientID %>';
if (cmdAuthoriseButton == args._postBackElement.id) {
// Show UpdateProgress for subscribe
onUpdateOfSubscribe();
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<div class="FormWrapper">
<div class="rowHeader">
</div>
<asp:UpdatePanel ID="updRegister" runat="server" UpdateMode="Conditional" >
<ContentTemplate>
<asp:Panel ID="pnlRegister" runat="server" Height="10px">
<div class="row" style="display:none;">
<asp:Label ID="Label7" runat="server" Text="Activity:" class="lbl"></asp:Label>
<asp:DropDownList ID="ddActivities" runat="server" CssClass="dd252" DataTextField="EventTitle" DataValueField="EventID">
</asp:DropDownList>
</div>
<div class="row">
<asp:Label ID="lblSName" runat="server" Text="Name:" class="lbl"></asp:Label>
<asp:TextBox ID="txtSName" runat="server" CssClass="txt"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" ErrorMessage="*" ControlToValidate="txtSName" ValidationGroup="ActivityReg" ></asp:RequiredFieldValidator>
</div>
<div class="row">
<asp:Label ID="lblSAge" runat="server" Text="Age:" class="lbl"></asp:Label>
<asp:TextBox ID="txtSAge" runat="server" CssClass="txt"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ErrorMessage="*" ControlToValidate="txtSAge" ValidationGroup="ActivityReg" ></asp:RequiredFieldValidator>
<asp:RangeValidator ID="RangeValidator1" runat="server" ErrorMessage="*" ControlToValidate="txtSAge" MaximumValue="100" MinimumValue="4"
ValidationGroup="ActivityReg" Type="Integer" ></asp:RangeValidator>
</div>
<div class="row">
<asp:Label ID="lblGMobile" runat="server" Text="Guardian Mobile:" class="lbl"></asp:Label>
<asp:TextBox ID="txtGMobile" runat="server" CssClass="txt"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator5" runat="server" ErrorMessage="*" ControlToValidate="txtGMobile" ValidationGroup="ActivityReg" ></asp:RequiredFieldValidator>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ErrorMessage="*" ControlToValidate="txtGMobile" ValidationGroup="ActivityReg" ></asp:RequiredFieldValidator><asp:RegularExpressionValidator ID="RegularExpressionValidator2" runat="server" ValidationGroup="ActivityReg"
ControlToValidate="txtGMobile" ErrorMessage="*" ValidationExpression="[0-9 ]{9,}"></asp:RegularExpressionValidator>
</div>
<div class="rowDouble">
<asp:Label ID="lblAddress" runat="server" Text="Address:" class="lbl"></asp:Label>
<asp:TextBox ID="txtAddress" runat="server" CssClass="txtDouble" TextMode="MultiLine"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ErrorMessage="*" ControlToValidate="txtAddress" ValidationGroup="ActivityReg" ></asp:RequiredFieldValidator>
</div>
<div class="row">
<asp:Button ID="btnRegister" CssClass="btn" runat="server"
ValidationGroup="ActivityReg" Text="Register" onclick="btnRegister_Click" />
</div>
</asp:Panel>
<div class="dSubMSG">
<asp:Label ID="lblMSG" runat="server" Text=""></asp:Label>
</div>
<div id="divImage" style="display:none" class="dSubAni">
<asp:Image ID="Image1" runat="server" ImageUrl="~/Images/ajax-loader-gray.png" Visible="true"/>
</div>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnRegister" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
<asp:UpdateProgress ID="updProgressRegister" runat="server" AssociatedUpdatePanelID="updRegister" >
<ProgressTemplate>
</ProgressTemplate>
</asp:UpdateProgress>
</div>
</form>
我有其他带有 UpdatePanel 和进度条的用户控件，我捕获了 ascy 回发的源并相应地隐藏或显示进度条。希望这会有所帮助..但你可能需要努力
【讨论】：