由于我将我的网站从 .NET 4.0 更改为 3.5 ModalPopup 无法正常工作。问题是没有显示错误消息。所以我不知道如何解决它。以前有人遇到过同样的问题吗?
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<div>
<asp:Button ID="btnpopup" runat="server" Text="Button" />
<asp:ModalPopupExtender ID="mpe" runat="server" TargetControlID="btnpopup" PopupControlID="pnlpopup"
CancelControlID="btnCancelpopup" EnableViewState="true" DropShadow="true" />
<asp:Panel ID="pnlpopup" runat="server" Width="400px">
test
<asp:Button ID="btnCancelpopup" runat="server" Text="Button" />
</asp:Panel>
</div>
</form>
</body>
</html>