ASP.NET/AJAX Updatepanel显示两次

本文介绍了ASP.NET/AJAX Updatepanel显示两次的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述 29岁程序员，3月因学历无情被辞！ 我很久没有触及ASP了，我开始记起原因了！ 我有一个包含转发器的更新面板，转发器项目包含一个按钮，我希望该按钮作为更新面板的异步回发触发器。 更新面板如下所示： < asp：UpdatePanel runat = server 可见 = true ID = pnlSproc UpdateMode = 条件 ChildrenAsTriggers = true > < ContentTemplate > 。 。 。 < asp：Repeater runat = server ID = rptParameters EnableViewState = true OnItemCreated = rptParameters_ItemCreated > < ItemTemplate > < tr > 。 。 。 < td > < asp：按钮 runat = server ID = btnAddParameter / > ; < / td > < / tr > < / ItemTemplate > < / asp：Repeater > < / tr > < / ContentTemplate > < / asp：UpdatePanel > 转发器的ItemCreated事件将按钮添加为异步触发器... protected void rptParameters_ItemCreated（ object 来源，RepeaterItem EventArgs e） { ScriptManager manager = ScriptManager.GetCurrent（ this ）; 按钮按钮=（按钮）e.Item.FindControl（ btnAddParameter）; if （button！= null ） { button.Click + = AddParameterClick; manager.RegisterAsyncPostBackControl（button）; } } 当事件触发时，所有相应的事件都按预期触发，但面板呈现两次 - 一次更新后的形式（页面比它应该更高）并且一次处于其原始形式和位置。 如果我将RegisterAsyncPostBackControl调用更改为RegisterPostBackControl，一切正常，因为我期望它但显然我得到了一整页我不想要的回帖。 有没有人遇到过类似的东西？它看起来像是导致渲染问题的异步回发（它发生在IE和Chrome中，我的标记看起来完全有效。我已经尝试将脚本管理器从页面移动到主机并且没有效果，要么。解决方案 解决方案 为什么要动态添加按钮作为触发器。你正在做因为你正在调用一个 AddParameterClick 的自定义事件。 无论你在这个事件中做什么都可以可在 ItemCommand [ ^ ]事件本身。您可以将 ItemCommand 事件声明为异步触发器。 通过RepeaterCommandEventArgs类 [ ^ ]，您可以获取有关从中获取命令的行的所有详细信息。 所以，摘要是...... 声明 ItemCommand 像触发器一样... < 触发器 > < asp：AsyncPostBackTrigger ControlID = rptParameters EventName = ItemCommand / > < / Triggers > 声明 ItemCommand 直放站。删除 ItemCreated ，这是不再需要的。 < ; asp：Repeater runat = server ID = rptParameters EnableViewState = true OnItemCommand = rptParameters_ItemCommand > 在 ItemCommand 内，做你想做的事在 AddParameterClick 里面做。 嗯，我知道使用表格有点顽皮（我真的不想在单个页面，内部Web表单的CSS路线上）但是更新面板被创建为div并且与表格混淆并且其中存在问题。 我把桌子换成div和段落后，一切都开始工作了。 故事的寓意：a捷径很少是捷径。 I haven't touched ASP in a long time and I'm starting to remember why!I have an update panel that contains a repeater, the repeater items contain a button and I want that button as an asynchronous post-back trigger for the update panel.The update panel looks like this:<asp:UpdatePanel runat="server" Visible="true" ID="pnlSproc" UpdateMode="Conditional" ChildrenAsTriggers="true"> <ContentTemplate> . . . <asp:Repeater runat="server" ID="rptParameters" EnableViewState="true" OnItemCreated="rptParameters_ItemCreated" > <ItemTemplate> <tr> . . . <td> <asp:Button runat="server" ID="btnAddParameter" /> </td> </tr> </ItemTemplate> </asp:Repeater> </tr> </ContentTemplate></asp:UpdatePanel>The ItemCreated event of the repeater adds the button as an asynchronous trigger ...protected void rptParameters_ItemCreated(object source, RepeaterItemEventArgs e){ ScriptManager manager = ScriptManager.GetCurrent(this); Button button = (Button)e.Item.FindControl("btnAddParameter"); if (button != null) { button.Click += AddParameterClick; manager.RegisterAsyncPostBackControl(button); }}When the event fires, all the appropriate events fire as expected but the panel is rendered twice - once in its updated form (higher up the page than it should be) and once in its original form and position.If I change the RegisterAsyncPostBackControl call to RegisterPostBackControl everything works as I would expect it to but obviously I get a full page postback which I don't want.Has anyone come across anything similar before? It certainly looks like it's the async postback that's causing the rendering problem (it occurs in both IE and Chrome and my mark-up looks completely valid. I've tried moving the script manager from the page to the master and that has no effect, either. 解决方案 SolutionWhy are you dynamically adding the button as a Trigger. You are doing it because you are calling one custom Event that is "AddParameterClick".Whatever you are doing inside this Event can be done inside the ItemCommand[^] Event itself. And you can declare ItemCommand Event as a Async Trigger.Through the RepeaterCommandEventArgs Class[^], you can fetch every details about the Row from which you got the Command.So, summary is...Declare the ItemCommand as a Trigger like...<Triggers> <asp:AsyncPostBackTrigger ControlID="rptParameters" EventName="ItemCommand" /></Triggers>Declare ItemCommand for the Repeater. Delete ItemCreated, which is not needed any more.<asp:Repeater runat="server" ID="rptParameters" EnableViewState="true" OnItemCommand="rptParameters_ItemCommand" >Inside the ItemCommand, do what you are trying to do inside the AddParameterClick.Well, I knew that using tables was a bit naughty (I really didn't want to go down the CSS route for a single page, internal web form) but the update panel gets created as a div and that gets confused with the table and therein lies the problem.As soon as I changed my table to divs and paragraphs, it all started working.The moral of the story: a short-cut is rarely a short-cut. 这篇关于ASP.NET/AJAX Updatepanel显示两次的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！ 上岸，阿里云！