Ch12, TIO p397: Exception in execution

mkaftor · January 24th, 2011, 12:43 PM

Following Setting Up the Filter TIO, I get the following excepton. No other errors otherwise. Can you help?

Thanks, Michael

The exception from the browser:

Quote:

Server Error in '/' Application.
--------------------------------------------------------------------------------
Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error:

Line 27:
Line 28: //execute either way: postbak or not
Line 29: switch (Page.Theme.ToLower())
Line 30: {
Line 31: //change for "darkgrey", if selected

Source File: d:\WroxBegASPNET35\PlanetWroxSite\MasterPages\Mast erPage.master.cs Line: 29
Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.]
MasterPage.Page_Load(Object sender, EventArgs e) in d:\WroxBegASPNET35\PlanetWroxSite\MasterPages\Mast erPage.master.cs:29
System.Web.Util.CalliHelper.EventArgFunctionCaller (IntPtr fp, Object o, Object t, EventArgs e) +14
System.Web.Util.CalliEventHandlerDelegateProxy.Cal lback(Object sender, EventArgs e) +35
System.Web.UI.Control.OnLoad(EventArgs e) +99
System.Web.UI.Control.LoadRecursive() +50
System.Web.UI.Control.LoadRecursive() +141
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +627

The markup for Reviews.aspx:

Quote:

<%@ Page Title="Lanical - Management - Reviews" Language="C#"
MasterPageFile="~/MasterPages/MasterPage.master"
AutoEventWireup="true"
CodeFile="Reviews.aspx.cs"
Inherits="Management_Reviews" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="cphMainContent" Runat="Server">

<asp:DropDownList ID="DropDownList1" runat="server"
DataSourceID="SqlDataSource1" DataTextField="Name" DataValueField="Id"
onselectedindexchanged="DropDownList1_SelectedInde xChanged"
AppendDataBoundItems="True"
AutoPostBack="true" >
<asp:ListItem Value="">Please make a selection</asp:ListItem>
</asp:DropDownList>

<asp:SqlDataSource ID="SqlDataSource1" runat="server"
ConnectionString="<%$ ConnectionStrings:PlanetWroxConnectionString1 %>"
SelectCommand="SELECT [Id], [Name] FROM [Genere] ORDER BY [SortOrder]">
</asp:SqlDataSource>
</asp:Content>

and the corresponding Reviews.cs file:

Quote:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class Management_Reviews : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
}
}

The markup for the ManagementMaster.master:

Quote:

<%@ Master Language="C#" AutoEventWireup="true"
CodeFile="ManagementMaster.master.cs"
Inherits="MasterPages_ManagementMaster" %>
<!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>
<asp:ContentPlaceHolder id="head" runat="server">
</asp:ContentPlaceHolder>
</head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
<div style="width: 200px; float:left;">
<ul>
<%--"." in href was changed to "~", mk 01-23-11--%>
<li><a href="~/Management/Default.aspx" runat="server">Management Home</a></li>
<li><a href="~/Management/Generes.aspx" runat="server">Manage Geners</a></li>
<li><a href="~/Management/Reviews.aspx" runat="server">Manage Reviews</a></li>
</ul>
</div>

<div style="width: 750px; float:left;">
<asp:ContentPlaceHolder id="cpMainContent" runat="server">

</asp:ContentPlaceHolder>
</div>
</form>
</body>
</html>

and last, MasterPage.master.cs:

Quote:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class MasterPage : System.Web.UI.MasterPage
{
protected void Page_Load(object sender, EventArgs e)
{
//if not postback
if (!Page.IsPostBack)
{
string selectedTheme = Page.Theme;
HttpCookie preferredTheme = Request.Cookies.Get("PreferredTheme");
if (preferredTheme != null)
{
selectedTheme = preferredTheme.Value;
}
if (lstPreferredTheme.Items.FindByValue(selectedTheme ) != null)
{
lstPreferredTheme.Items.FindByValue(selectedTheme) .Selected = true;
}
}
//execute either way: postbak or not
switch (Page.Theme.ToLower())
{
//change for "darkgrey", if selected
case "darkgrey":
Menu1.Visible = false;
TreeView1.Visible = true;
break;
//otherwise, initialize for "monochrome"
default:
Menu1.Visible = true;
TreeView1.Visible = false;
break;
}
}
protected void lstPreferredTheme_SelectedIndexChanged(object sender, EventArgs e)
{
//declare and create the cookie
HttpCookie preferredTheme = new HttpCookie("PreferredTheme");
//set the experation time of the cookie: 3 months
preferredTheme.Expires = DateTime.Now.AddMonths(3);
//write to the cookie: the user selected theme
preferredTheme.Value = lstPreferredTheme.SelectedValue;
//add the cookie to the cookie collection
Response.Cookies.Add(preferredTheme);
//redirect the request to the same page, thereby reset the theme immediately
Response.Redirect(Request.Url.ToString());
}
}

Imar · January 24th, 2011, 12:51 PM

Hi there,

Did you set the theme to an empty string in the web.config file in the Management folder as instructed on page 388 and 389?

If that doesn't help, can you post the code for your two web.config files?

Cheers,

Imar

mkaftor · January 24th, 2011, 01:10 PM

Here is the code:

web.config under Management folder:

Quote:

<?xml version="1.0"?>

<configuration>
<appSettings/>
<connectionStrings/>
<system.web>
<pages theme=""></pages>
</system.web>
</configuration>

and web.config from the application root:

Quote:

<?xml version="1.0"?>

<configuration>
<configSections>
<sectionGroup name="system.web.extensions" type="System.Web.Configuration.SystemWebExtensions SectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<sectionGroup name="scripting" type="System.Web.Configuration.ScriptingSectionGro up, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<section name="scriptResourceHandler" type="System.Web.Configuration.ScriptingScriptReso urceHandlerSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication"/>
<sectionGroup name="webServices" type="System.Web.Configuration.ScriptingWebService sSectionGroup, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<section name="jsonSerialization" type="System.Web.Configuration.ScriptingJsonSerial izationSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="Everywhere" />
<section name="profileService" type="System.Web.Configuration.ScriptingProfileSer viceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication" />
<section name="authenticationService" type="System.Web.Configuration.ScriptingAuthentica tionServiceSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication" />
<section name="roleService" type="System.Web.Configuration.ScriptingRoleServic eSection, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" allowDefinition="MachineToApplication" />
</sectionGroup>
</sectionGroup>
</sectionGroup>
</configSections>

<appSettings/>
<connectionStrings>
<add name="PlanetWroxConnectionString1"
connectionString="Data Source=.\SQLEXPRESS;
AttachDbFilename=|DataDirectory|\PlanetWrox.mdf;
Integrated Security=True;
User Instance=True"
providerName="System.Data.SqlClient" />
</connectionStrings>
<system.web>





<compilation debug="true"> 
<assemblies>
<add assembly="System.Core, Version=3.5.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
<add assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add assembly="System.Data.DataSetExtensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
<add assembly="System.Xml.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089"/>
</assemblies>
</compilation>

<authentication mode="Windows" />



<pages theme="Monochrome" >


<controls>
<add tagPrefix="Lanical" tagName="Banner" src="~/Controls/Banner.ascx" />
<add tagPrefix="asp" namespace="System.Web.UI" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add tagPrefix="asp" namespace="System.Web.UI.WebControls" assembly="System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
</controls>
</pages>
<httpHandlers>
<remove verb="*" path="*.asmx"/>
<add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFact ory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHandlerFact ory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" validate="false"/>
</httpHandlers>
<httpModules>
<add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
</httpModules>

</system.web>
<system.codedom>
<compilers>
<compiler language="c#;cs;csharp" extension=".cs" warningLevel="4"
type="Microsoft.CSharp.CSharpCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<providerOption name="CompilerVersion" value="v3.5"/>
<providerOption name="WarnAsError" value="false"/>
</compiler>
<compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" warningLevel="4"
type="Microsoft.VisualBasic.VBCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<providerOption name="CompilerVersion" value="v3.5"/>
<providerOption name="OptionInfer" value="true"/>
<providerOption name="WarnAsError" value="false"/>
</compiler>
</compilers>
</system.codedom>


<system.webServer>
<validation validateIntegratedModeConfiguration="false"/>
<modules>
<remove name="ScriptModule" />
<add name="ScriptModule" preCondition="managedHandler" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
</modules>
<handlers>
<remove name="WebServiceHandlerFactory-Integrated"/>
<remove name="ScriptHandlerFactory" />
<remove name="ScriptHandlerFactoryAppServices" />
<remove name="ScriptResource" />
<add name="ScriptHandlerFactory" verb="*" path="*.asmx" preCondition="integratedMode"
type="System.Web.Script.Services.ScriptHandlerFact ory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add name="ScriptHandlerFactoryAppServices" verb="*" path="*_AppService.axd" preCondition="integratedMode"
type="System.Web.Script.Services.ScriptHandlerFact ory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
<add name="ScriptResource" preCondition="integratedMode" verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
</handlers>
</system.webServer>
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="System.Web.Extensions" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
</dependentAssembly>
<dependentAssembly>
<assemblyIdentity name="System.Web.Extensions.Design" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="3.5.0.0"/>
</dependentAssembly>
</assemblyBinding>
</runtime>
<system.net>
<mailSettings>
<smtp deliveryMethod="Network"
from="Michael Kaftor<[email protected]>">
<network host="smtp.live.com"
userName="[email protected]"
password="live9936"/>
</smtp>
</mailSettings>
</system.net>
</configuration>

Imar · January 24th, 2011, 01:33 PM

Just saw something else:

<%@ Page Title="Lanical - Management - Reviews" Language="C#"
MasterPageFile="~/MasterPages/MasterPage.master"
AutoEventWireup="true"
CodeFile="Reviews.aspx.cs"
Inherits="Management_Reviews" %>

The pages in your Management section should be based on ManagementMaster.master, not on MasterPage.master

Does that fix the problem? If not, can you zip up the site and send it to me? You can find out my e-mail address by sending me a message through the Contact page of my web site: http://imar.spaanjaars.com/about to which I'll reply.

Cheers,

Imar

mkaftor · January 24th, 2011, 02:54 PM

Thanks -- indeed I based the page on the wrong master.

And as a contribution on my part, would the 5th line from the bottom, p395, should read:
. . . for the connection string that is listed by the name PlanetWroxConnectionString1, instead of
. . . for the connection string that listens the name PlanetWroxConnectionString1,
?????

"listens" does not make sense to me???

Imar · January 24th, 2011, 04:41 PM

The text says "listens to". Of course it doesn't actually listen, but you can access it by using its name ;-) E.g. you call PlanetWroxConnectionString1 and you get the connection string back....

Imar
.

Imar · January 25th, 2011, 04:57 AM

Oh, BTW: it's probably a good idea to remove your mail settings from the config file you posted here ;-)

Cheers,

Imar