Chapter 6

martinedhotman · October 22nd, 2015, 10:03 AM

When attempting the 'Try it out' I'm getting the following error message: 'ASP.masterpages_frontend_master' does not contain a definition for 'ThemeList_SelectedIndexChanged' and no extension method 'ThemeList_SelectedIndexChanged' accepting a first argument of type 'ASP.masterpages_frontend_master' could be found (are you missing a using directive or an assembly reference?)
What have I missed? I've compared my version of FrontEnd.Master & the code behind to the version supplied and could not find the error.
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Compiler Error Message: CS1061: 'ASP.masterpages_frontend_master' does not contain a definition for 'ThemeList_SelectedIndexChanged' and no extension method 'ThemeList_SelectedIndexChanged' accepting a first argument of type 'ASP.masterpages_frontend_master' could be found (are you missing a using directive or an assembly reference?)
Source Error:
Line 24: <asp:DropDownList ID="ThemeList" runat="server" AutoPostBack="True" OnSelectedIndexChanged="ThemeList_SelectedIndexCha nged">

Imar · October 22nd, 2015, 06:58 PM

Hi there,

Can you post your code?

Imar

martinedhotman · October 23rd, 2015, 03:12 AM

I'm using VS 2015. Theme 'Monochrome' would not load, so I renamed it 'BlueGrey'

Code:

<%@ Master Language="C#" AutoEventWireup="true" CodeFile="FrontEnd.master.cs" Inherits="MasterPages_FrontEnd" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
    <asp:ContentPlaceHolder id="head" runat="server">
    </asp:ContentPlaceHolder>
</head>
<body>
    <form id="form1" runat="server">
        <div id="PageWrapper">
            <header><a href="/"></a></header>
            <nav>Menu Goes Here</nav>
            <section id="MainContent">
                <asp:ContentPlaceHolder ID="cpMainContent" runat="server">
                    This is default text that shows up in content pages that don't explicitly override it.
                </asp:ContentPlaceHolder>
            </section>
            <aside id="Sidebar">
                Select a theme
        <br />
                <asp:DropDownList ID="ThemeList" runat="server" AutoPostBack="True" OnSelectedIndexChanged="ThemeList_SelectedIndexChanged">
                    <asp:ListItem>BlueGrey</asp:ListItem>
                    <asp:ListItem>DarkGrey</asp:ListItem>
                </asp:DropDownList>
            </aside>
            <footer>Footer Goes Here</footer>
        </div>
    </form>
</body>
</html>

martinedhotman · October 23rd, 2015, 04:55 AM

I've changed the dropdown list ID from ThemeList to ThemeSel and this resolved the problem.

I'm loving the book by the way.

Imar · October 24th, 2015, 03:04 PM

The ID of the control shouldn't matter; it's the name of the method that is assigned in OnSelectedIndexChanged that is relevant. It needs to have a matching method in the code behind.

Imar