<%@ Assembly Name="Microsoft.SharePoint, Version=16.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c"%> <%@ Page Language="C#" Inherits="Microsoft.SharePoint.WebPartPages.WikiEditPage" MasterPageFile="~masterurl/default.master"      MainContentID="PlaceHolderMain" %> <%@ Import Namespace="Microsoft.SharePoint.WebPartPages" %> <%@ Register Tagprefix="SharePoint" Namespace="Microsoft.SharePoint.WebControls" Assembly="Microsoft.SharePoint, Version=16.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %> <%@ Register Tagprefix="Utilities" Namespace="Microsoft.SharePoint.Utilities" Assembly="Microsoft.SharePoint, Version=16.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %> <%@ Import Namespace="Microsoft.SharePoint" %> <%@ Assembly Name="Microsoft.Web.CommandUI, Version=16.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<%@ Register Tagprefix="WebPartPages" Namespace="Microsoft.SharePoint.WebPartPages" Assembly="Microsoft.SharePoint, Version=16.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>
<asp:Content ContentPlaceHolderId="PlaceHolderPageTitle" runat="server">
    <SharePoint:ProjectProperty Property="Title" runat="server"/> - <SharePoint:ListItemProperty runat="server"/>
</asp:Content>
<asp:Content ContentPlaceHolderId="PlaceHolderPageImage" runat="server"><SharePoint:AlphaImage ID=onetidtpweb1 Src="/_layouts/15/images/wiki.png?rev=41" Width=145 Height=54 Alt="" Runat="server" /></asp:Content>
<asp:Content ContentPlaceHolderId="PlaceHolderAdditionalPageHead" runat="server">
    <meta name="CollaborationServer" content="SharePoint Team Web Site" />
    <SharePoint:ScriptBlock runat="server">
    var navBarHelpOverrideKey = "WSSEndUser";
    </SharePoint:ScriptBlock>
    <SharePoint:RssLink runat="server" />
    </asp:Content>
<asp:Content ContentPlaceHolderId="PlaceHolderMiniConsole" runat="server">
    <SharePoint:FormComponent TemplateName="WikiMiniConsole" ControlMode="Display" runat="server" id="WikiMiniConsole"/>
</asp:Content>
<asp:Content ContentPlaceHolderId="PlaceHolderLeftActions" runat="server">
    <SharePoint:RecentChangesMenu runat="server" id="RecentChanges"/>
</asp:Content>
<asp:Content ContentPlaceHolderId="PlaceHolderMain" runat="server">
 
        //вот мое единственное изменение в коде: убрал все из этого блока и вставил мэссидж бокс
    Response.Write("<script type="text/javascript">alert('Hello, world!');</script>"); 
</asp:Content>