Question

您好我需要在udate面板异步回发后拦截服务器回调并确定哪个面板发起了请求。代码非常简单：

Sys.WebForms.PageRequestManager.getInstance().add_pageLoaded(InterceptUpdateCallback);

function InterceptUpdateCallback(sender, args)
{
    var updatedPanels = args.get_panelsUpdated();    
    for (idx = 0; idx < updatedPanels.length; idx++) {
        if (updatedPanels[idx].id == "myUpdatePanel") {            
            StartSmth();
            break;
        }
      }
}

当UpdatePanel不在另一个UpdatePanel中时，它可以正常工作。但是当它在另一个UpdatePanel内时，updatedPanels [idx] .id具有父Updatepanel id。那么我怎样才能获得启动请求的UpdatePanel的id（内部UpdatePanel）？感谢名单

Answer 1

你走了：

function InterceptUpdateCallback(sender, args) {
 if (sender._postBackSettings)
    alert(sender._postBackSettings.panelID);
 else
    alert('first load');    
}

<强>更新

<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
    protected void LinkButtons_Click(object sender, EventArgs e)
    {
        LabelMain.Text = LabelSub1.Text = LabelSub2.Text = LabelSub3.Text = string.Format("{0} Updated By {1}", DateTime.Now, ((Control)sender).ID);
    }
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <style type="text/css">
        body { font-family: Tahoma;}
        fieldset { padding: 15px; }
        fieldset a 
        {
            float: right;
            clear: none;
            display: block;
            margin: 10px;
        }
        fieldset span
        {
            display: block;
            margin-top: 20px;
            margin-bottom: 20px;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <asp:ScriptManager ID="ScriptManager1" runat="server" />
    <script type="text/javascript">
        function pageLoaded(sender, args) {
            if (sender._postBackSettings) {
                var panelId = sender._postBackSettings.panelID.split('|')[0];
                if (panelId == sender._scriptManagerID) {
                    var updatedPanels = args.get_panelsUpdated();
                    var affectedPanels = "Affected Panels:\n";
                    for(var x=0;x<updatedPanels.length;x++)
                        affectedPanels+= updatedPanels[x].id + "\n";
                    alert("Request initiated by ScriptManager\n\nMight be an async trigger, or child of an update panel with children as triggers set to false.\n\n"+affectedPanels);
                }
                else
                    alert("Request initiated by: " + panelId);
            }
        }
        Sys.WebForms.PageRequestManager.getInstance().add_pageLoaded(pageLoaded);
    </script>

    <asp:LinkButton ID="UpdateMain" runat="server" Text="UpdateMain" OnClick="LinkButtons_Click"></asp:LinkButton>,
    <asp:LinkButton ID="UpdateSub1" runat="server" Text="UpdateSub1" OnClick="LinkButtons_Click"></asp:LinkButton>,
    <asp:LinkButton ID="UpdateSub2" runat="server" Text="UpdateSub2" OnClick="LinkButtons_Click"></asp:LinkButton>,
    <asp:LinkButton ID="UpdateSub3" runat="server" Text="UpdateSub3" OnClick="LinkButtons_Click"></asp:LinkButton>
    <br />
    <br />
    <asp:UpdatePanel ID="Main" runat="server" ChildrenAsTriggers="false" UpdateMode="Conditional">
        <ContentTemplate>
            <fieldset>
                <asp:LinkButton ID="LinkButton1" runat="server" Text="LinkButton1" OnClick="LinkButtons_Click"></asp:LinkButton>
                <legend>Main -  Update Mode:Conditional, Children As Triggers:False</legend>
                <asp:Label ID="LabelMain" runat="server" Text="LabelMain"></asp:Label>
                <asp:UpdatePanel ID="Sub1" runat="server" UpdateMode="Always" ChildrenAsTriggers="true">
                    <ContentTemplate>
                        <fieldset>
                            <asp:LinkButton ID="LinkButton2" runat="server" Text="LinkButton2" OnClick="LinkButtons_Click"></asp:LinkButton>
                            <legend>Sub1 - Update Mode:Always, Children As Triggers:True</legend>
                            <asp:Label ID="LabelSub1" runat="server" Text="LabelSub1"></asp:Label>
                            <asp:UpdatePanel ID="Sub2" runat="server"  UpdateMode="Always" ChildrenAsTriggers="true">
                                <ContentTemplate>
                                    <fieldset>
                                        <asp:LinkButton ID="LinkButton3" runat="server" Text="LinkButton3" OnClick="LinkButtons_Click"></asp:LinkButton>
                                        <legend>Sub2 - Update Mode:Always, Children As Triggers:True</legend>
                                        <asp:Label ID="LabelSub2" runat="server" Text="LabelSub2"></asp:Label>
                                    </fieldset>
                                </ContentTemplate>
                                <Triggers>
                                    <asp:AsyncPostBackTrigger ControlID="UpdateSub2" />
                                </Triggers>
                            </asp:UpdatePanel>                            
                        </fieldset>                        
                    </ContentTemplate>
                    <Triggers>
                        <asp:AsyncPostBackTrigger ControlID="UpdateSub1" />
                    </Triggers>
                </asp:UpdatePanel>
                <asp:UpdatePanel ID="Sub3" runat="server" ChildrenAsTriggers="false" UpdateMode="Conditional">
                    <ContentTemplate>

                        <fieldset>
                            <asp:LinkButton ID="LinkButton4" runat="server" Text="LinkButton4" OnClick="LinkButtons_Click"></asp:LinkButton>
                            <legend>Sub3 - Update Mode:Conditional, Children As Triggers:False</legend>
                            <asp:Label ID="LabelSub3" runat="server" Text="LabelSub3"></asp:Label>
                        </fieldset>                        
                    </ContentTemplate>
                    <Triggers>
                        <asp:AsyncPostBackTrigger ControlID="UpdateSub3" />
                    </Triggers>
                </asp:UpdatePanel>
            </fieldset>
        </ContentTemplate>
        <Triggers>
            <asp:AsyncPostBackTrigger ControlID="UpdateMain" />
        </Triggers>
    </asp:UpdatePanel>
    </form>
</body>
</html>

Answer 2

我会猜到这个。

在外部（或两者）UpdateMode = Conditional上设置UpdatePanel是否有帮助？我认为问题在于您只获得了“最外层”的更新面板，如果您没有将UpdateMode设置为Conditional，外部面板也会更新（即使您单击内部面板中的某些内容;见第二篇参考资料）。

供参考

请注意，如果我删除了该属性 UpdateMode =有条件的 UpdatePanel1（父级），两个标签会得到更新。

来自ASP.NET 2.0 AJAX Extensions Update Panel - Nested Update Panel

和

设置为Always时，UpdatePanel为从每个回发中更新在页面的任何位置，所以从控件在面板内部，在其他面板内或者只是在页面上。

来自Remember to set UpdatePanel's UpdateMode to Conditional

Answer 3

最后我找到了解决方案：问题是我有一个子UpdatePanel的触发控件（Button），它实际上在这个Update面板之外，在父UpdatePanel里面（抱歉，我没有注意到）。如果你将Button放在子UpdatePanel中 - 一切正常。

如何获取启动回发的Updatepanel的ID

3 个答案: