我的aspx页面与ScriptManager有关。
如果我使用单个脚本管理器，则显示错误
'ScriptManager'类型的控件'maincontent_ctl00'必须放在带有runat = server的表单标签内。
如果我在表单标记中使用ScriptManager，则会显示
只能将一个ScriptManager实例添加到页面
如果我使用单曲脚本管理器然后发出，如果我使用两个然后仍然发出。
<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="chat.aspx.cs" Inherits="ChatManager.chat" MaintainScrollPositionOnPostback="true" ValidateRequest="false" %>
<asp:Content ID="Content1" ContentPlaceHolderID="maincontent" runat="server">
<script>
function playSound() {
document.getElementById("audioId").play();
}
</script>
<audio id="audioId" src="Sound/tone.wav" style="display: none" controls="controls" preload="auto"></audio>
<asp:ScriptManager runat ="server" ></asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel2" runat="server">
<ContentTemplate>
<asp:Timer ID="Timer1" runat="server" Interval="3000"
OnTick="Timer1_Tick">
</asp:Timer>
<asp:Panel ID="Panel2" runat="server">
<div>
<h5 class="alert alert-success" style="text-align: center">
<span>Hello
<%=Server.HtmlEncode(CurrentSender.Text).ToUpper()%> !!</span>
<asp:Button ID="Logout" runat="server" Text="logout"
OnClick="logout_Click" CssClass="btn btn-warning" Height="30px" />
</h5>
</div>
</asp:Panel>
<asp:Panel ID="Panel1" runat="server">
<div style="max-height: 520px; padding: 5px" class="col-lg-12 pre-scrollable">
<asp:Label ID="CurrentSender" runat="server" Text="" Visible="false"></asp:Label>
<asp:Label ID="CurrentRecevier" runat="server" Text="" Visible="false"></asp:Label>
<asp:SqlDataSource ID="SqlDataSource3" runat="server" ConnectionString='<%$ ConnectionStrings:RegistrationConnectionString %>' SelectCommand="SELECT [MsgSender] FROM [MsgTable] WHERE (([RecevierSeen] = 0) AND ([MsgReceiver] = @MsgReceiver))">
<SelectParameters>
<asp:ControlParameter ControlID="CurrentSender" PropertyName="Text" Name="MsgReceiver" Type="String"></asp:ControlParameter>
</SelectParameters>
</asp:SqlDataSource>
<div class="panel panel-danger">
<div class="panel-heading">
<span>Unread Messages </span>
<span>
<asp:Label ID="UnreadMsgCountLabel" runat="server" CssClass="badge"></asp:Label>
</span>
</div>
<div class="list-group">
<asp:DataList ID="DataList4" runat="server" DataSourceID="SqlDataSource3" Width="100%">
<ItemTemplate>
<asp:LinkButton Text='<%# Eval("MsgSender") %>' runat="server" ID="MsgSenderLabel" OnClick="UsernameLabel_Click" CssClass="list-group-item" />
</ItemTemplate>
</asp:DataList>
</div>
</div>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString='<%$ ConnectionStrings:RegistrationConnectionString %>' SelectCommand="SELECT [Username] FROM [UserDatabase] WHERE ([Username] <> @Username) AND OnlineStatus = 1">
<SelectParameters>
<asp:ControlParameter ControlID="CurrentSender" PropertyName="Text" Name="Username" Type="String"></asp:ControlParameter>
</SelectParameters>
</asp:SqlDataSource>
<div class="panel panel-success">
<div class="panel-heading">Online Users</div>
<asp:DataList ID="DataList1" runat="server" DataSourceID="SqlDataSource1" Width="100%">
<ItemTemplate>
<div class="list-group-item">
<asp:LinkButton Text='<%# Eval("Username") %>' runat="server" ID="UsernameLabel" OnClick="UsernameLabel_Click" CssClass=" " />
<div class="OnlineCSS" />
</div>
</ItemTemplate>
</asp:DataList>
</div>
<asp:SqlDataSource ID="SqlDataSource2" runat="server" ConnectionString='<%$ ConnectionStrings:RegistrationConnectionString %>' SelectCommand="SELECT [Username] FROM [UserDatabase] WHERE ([Username] <> @Username) AND (OnlineStatus = 0 or OnlineStatus is null)">
<SelectParameters>
<asp:ControlParameter ControlID="CurrentSender" PropertyName="Text" Name="Username" Type="String"></asp:ControlParameter>
</SelectParameters>
</asp:SqlDataSource>
<div class="panel panel-info">
<div class="panel-heading">Offline Users</div>
<asp:DataList ID="DataList3" runat="server" DataSourceID="SqlDataSource2" Width="100%">
<ItemTemplate>
<div class="list-group-item">
<asp:LinkButton Text='<%# Eval("Username") %>' runat="server" ID="UsernameLabel" OnClick="UsernameLabel_Click" />
<div class="OfflineCSS"></div>
</div>
</ItemTemplate>
</asp:DataList>
</div>
</div>
</asp:Panel>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger EventName="Tick" ControlID="Timer1" />
</Triggers>
</asp:UpdatePanel>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<div>
<h4 style="text-align: center" class="alert alert-info"><%= GetWelcomeBanner(CurrentRecevier.Text)%></h4>
<span style="float: right"></span>
</div>
<asp:Panel runat="server" ID="chatPanel">
<div style="vertical-align: middle; min-height: 480px;" class="pre-scrollable">
<div>
<asp:DataList ID="DataList2" runat="server" Font-Bold="False" Font-Italic="False" Font-Overline="False" Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center" RepeatLayout="Table">
<ItemTemplate>
<div class="<%#GetStyleForMsgList(Eval("MsgSender").ToString()) %> MainChatListClass">
<asp:Label ID="Label1" runat="server" Text='<%# GetPerfactName(Eval("MsgSender").ToString()) %>'></asp:Label>
<asp:Label ID="Label2" runat="server" Text='<%# Eval("ChatMsg") %>'></asp:Label>
</div>
</ItemTemplate>
</asp:DataList>
</div>
</div>
</asp:Panel>
</ContentTemplate>
</asp:UpdatePanel>
<div style="padding: 5px 15px 5px 5px">
<asp:Panel ID="MsgPanel" runat="server" DefaultButton="sendBTN">
<asp:UpdatePanel ID="UpdatePanel3" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<script>
function loadingIconVisible() {
document.getElementById('<%=LoadingImage.ClientID%>').style.opacity = 1;
}
</script>
<div>
<form runat ="server" >
<asp:ScriptManager ID="ScriptManager11" runat ="server" ></asp:ScriptManager>
<table style="width: 120%">
<tr>
<td>
<asp:TextBox ID="MSGTextBox" runat="server" placeholder="Enter message" CssClass="form-control" Width="100%"></asp:TextBox>
</td>
<td>
<asp:Button ID="sendBTN" runat="server" Text="Send" OnClick="sendBTN_Click" CssClass="btn btn-default" Width="30%" OnClientClick="loadingIconVisible()" />
</td>
</tr>
</table>
<asp:Image ID="LoadingImage" runat="server" ImageUrl="~/images/loadingIcon.gif" ImageAlign="Right" />
</form>
</div>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Panel>
</div>
<style>
.SenderClass {
left: 55%;
background: #0b59ce;
color: #ffffff;
border: 1px solid #0b59ce;
}
.ReceiverClass {
left: -55%;
background: #c46909;
color: #ffffff;
border: 1px solid #c46909;
}
.MainChatListClass {
padding: 5px;
width: 250px;
position: relative;
border-radius: 5px;
word-wrap: break-word;
margin-top: 5px;
}
.SenderClass::after {
content: ' ';
position: absolute;
width: 0;
height: 0;
left: 243px;
top: 0px;
border: 10px solid;
border-color: transparent transparent #0b59ce #0b59ce;
}
.ReceiverClass::after {
content: ' ';
position: absolute;
width: 0;
height: 0;
right: 243px;
top: 3px;
border: 10px solid;
border-color: #c46909 #c46909 transparent transparent;
}
</style>
</asp:Content>
答案 0 :(得分：0)
您需要使用ScriptManagerProxy（也在ScriptManager下方的工具箱中列出），这正是如此。
https://msdn.microsoft.com/en-us/library/system.web.ui.scriptmanagerproxy(v=vs.110).aspx
从官方文档（见上面的链接）：
网页只能直接包含一个ScriptManager控件 在页面上或间接在嵌套或父组件内。该 ScriptManagerProxy控件允许您添加脚本和服务 内容页面和用户控件（如果是母版页或主页） 已包含ScriptManager控件。
答案 1 :(得分：0)
内容页面中有两个脚本管理器。
<asp:ScriptManager runat ="server" ></asp:ScriptManager>
and
<asp:ScriptManager ID="ScriptManager11" runat ="server" ></asp:ScriptManager>
删除第二个并检查。如果您还有其他脚本管理器，请检查母版页。