ASP.NET 4 Unleased - p 119 ppt

{ font-size:12px; text-align:left; padding:10px; } .login_button { border:solid 1px black; padding:3px; } Show Login The page in Listing 26.6 uses Cascading Style Sheets CSS to

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{

font-size:12px;

text-align:left;

padding:10px;

}

.login_button

{

border:solid 1px black;

padding:3px;

}

</style>

<title>Show Login</title>

</head>

<body>

<div>

<asp:Login

id=”Login1”

InstructionText=”Please log in before

accessing the premium section of our Website.”

TitleText=”Log In”

TextLayout=”TextOnTop”

LoginButtonText=”Log In”

DisplayRememberMe=”false”

CssClass=”login”

TitleTextStyle-CssClass=”login_title”

InstructionTextStyle-CssClass=”login_instructions”

LoginButtonStyle-CssClass=”login_button”

Runat=”server” />

</div>

</form>

</body>

</html>

The page in Listing 26.6 uses Cascading Style Sheets (CSS) to change the appearance of the

login form rendered by the Login control By taking advantage of Cascading Style Sheets,

you can customize the appearance of the Login control in any way that you can imagine

NOTE

For the complete list of properties supported by the Login control, see the Microsoft

.NET Framework SDK Documentation

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Automatically Redirecting a User to the Referring Page

If you request a page that you are not authorized to view, the ASP.NET Framework

auto-matically redirects you to the Login.aspx page After you log in successfully, you are

redi-rected back to the original page that you requested

When you are redirected to the Login.aspx page, a query string parameter named

ReturnUrl is automatically added to the page request This query string parameter

contains the path of the page that you originally requested The Login control uses the

ReturnUrl parameter when redirecting you back to the original page

You need to be aware of two special circumstances First, if you request the Login.aspx

page directly, a ReturnUrl parameter is not passed to the Login.aspx page In that case,

after you successfully log in, you are redirected to the Default.aspx page

Second, if you add the Login control to a page other than the Login.aspx page, the

ReturnUrl query string parameter is ignored In this case, you need to set the Login

control’s DestinationPageUrl property When you successfully log in, you are redirected

to the URL represented by this property If you don’t supply a value for the

DestinationPageUrl property, the same page is reloaded

Automatically Hiding the Login Control from Authenticated Users

Some websites display a login form at the top of every page That way, registered users can

log in at any time to view additional content The easiest way to add a Login control to all

the pages in an application is to take advantage of Master Pages If you add a Login

control to a Master Page, the Login control is included in every content page that uses the

Master Page

You can change the layout of the Login control by modifying the Login control’s

Orientation property If you set this property to the value Horizontal, the Username and

Password text boxes are rendered in the same row

If you include a Login control in all your pages, you should also modify the Login

control’s VisibleWhenLoggedIn property If you set this property to the value False, the

Login control is not displayed when a user has already authenticated

For example, the Master Page in Listing 26.7 contains a Login control that has both its

Orientation and VisibleWhenLoggedIn properties set

<%@ Master Language=”C#” %>

<!DOCTYPE html PUBLIC “-//W3C//DTD XHTML 1.0 Transitional//EN”

“http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd”>

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html

{

background-color:silver;

}

.content

{

margin:auto;

width:650px;

background-color:white;

padding:10px;

}

.login

{

font:10px Arial,Sans-Serif;

margin-left:auto;

}

.login input

{

font:10px Arial,Sans-Serif;

}

</style>

<title>My Website</title>

</head>

<body>

<asp:Login

id=”Login1”

Orientation=”Horizontal”

VisibleWhenLoggedIn=”false”

DisplayRememberMe=”false”

TitleText=””

CssClass=”login”

<hr />

<asp:contentplaceholder

id=”ContentPlaceHolder1”

runat=”server”>

</asp:contentplaceholder>

</div>

</form>

</body>

</html>

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The content page in Listing 26.8 uses the Master Page in Listing 26.7 (see Figure 26.4)

When you open the page in a browser, the Login control is hidden after you successfully

log in to the application

<%@ Page Language=”C#” MasterPageFile=”~/LoginMaster.master” %>

<asp:Content

ID=”Content1”

ContentPlaceHolderID=”ContentPlaceHolder1”

Runat=”Server”>

<h1>Welcome to our Website!</h1>

</asp:Content>

Using a Template with the Login Control

If you need to completely customize the appearance of the Login control, you can use a

template The Login control includes a LayoutTemplate property that enables you to

customize the layout of the controls rendered by the Login control

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When you create a Layout template, you can add controls to the template that have the

following IDs:

UserName

Password

RememberMe

FailureText

You also need to add a Button control that includes a CommandName property with the

value Login

The page in Listing 26.9 illustrates how you can use a LayoutTemplate to customize the

appearance of the Login control (see Figure 26.5)

<%@ Page Language=”C#” %>

.loginError

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{

color:red;

font:bold 14px Arial,Sans-Serif;

}

</style>

<title>Login Template</title>

</head>

<body>

<div>

<asp:Login

id=”Login1”

Runat=”server”>

<asp:Label

id=”FailureText”

EnableViewState=”false”

CssClass=”loginError”

<br />

<asp:Label

id=”lblUserName”

AssociatedControlID=”UserName”

Text=”User Name:”

<br />

<asp:TextBox

id=”UserName”

<asp:Label

id=”lblPassword”

AssociatedControlID=”Password”

Text=”Password:”

<br />

<asp:TextBox

id=”Password”

TextMode=”Password”

<asp:Button

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id=”btnLogin”

Text=”Login”

CommandName=”Login”

</LayoutTemplate>

</asp:Login>

</div>

</form>

</body>

</html>

Performing Custom Authentication with the Login Control

By default, the Login control uses ASP.NET Membership to authenticate a username and

password If you need to change this default behavior, you can handle the Login control’s

Authenticate event

Imagine, for example, that you are building a simple application and you want to store a

list of usernames and passwords in the web configuration file The web configuration file

in Listing 26.10 contains the credentials for two users named Bill and Ted

<?xml version=”1.0” encoding=”utf-8”?>

<system.web>

<forms>

</credentials>

</forms>

</authentication>

</system.web>

</configuration>

The page in Listing 26.11 contains a Login control that authenticates users against the list

of usernames and passwords stored in the web configuration file

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protected void Login1_Authenticate(object sender, AuthenticateEventArgs e)

{

string userName = Login1.UserName;

string password = Login1.Password;

e.Authenticated = FormsAuthentication.Authenticate(userName, password);

}

</script>

<title>Login Custom</title>

</head>

<body>

<div>

<asp:Login

id=”Login1”

OnAuthenticate=”Login1_Authenticate”

</div>

</form>

</body>

</html>

The page in Listing 26.11 includes a method that handles the Login control’s

Authenticate event The second parameter passed to the Authenticate event handler is an

instance of the AuthenticateEventArgs class This class includes the following property:

Authenticated

If you assign the value True to this property, the Login control authenticates the user

In Listing 26.11, the FormsAuthentication.Authenticate() method is called to check for

a username and password in the web configuration file that matches the username and

password entered into the login form The value returned from this method is assigned to

the AuthenticateEventArgs.Authenticated property

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Using the CreateUserWizard Control

The CreateUserWizard control renders a user registration form If a user successfully

submits the form, a new user is added to your website In the background, the

CreateUserWizard control uses ASP.NET membership to create the new user

The CreateUserWizard control supports a large number of properties (too many to list

here) that enable you to modify the appearance and behavior of the control For example,

the page in Listing 26.12 uses several of the CreateUserWizard properties to customize the

appearance of the form rendered by the control

.createUser

{

width:350px;

font:14px Verdana,Sans-Serif;

background-color:lightblue;

padding:4px;

}

.createUser_title

{

background-color:darkblue;

color:white;

font-weight:bold;

}

.createUser_instructions

{

font-size:12px;

text-align:left;

padding:10px;

}

.createUser_button

{

padding:3px;

}

</style>

<title>Show CreateUserWizard</title>

</head>

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<body>

<div>

<asp:CreateUserWizard

id=”CreateUserWizard1”

ContinueDestinationPageUrl=”~/Default.aspx”

InstructionText=”Please complete the following form

to register at this Website.”

CompleteSuccessText=”Your new account has been

created Thank you for registering.”

CssClass=”createUser”

TitleTextStyle-CssClass=”createUser_title”

InstructionTextStyle-CssClass=”createUser_instructions”

CreateUserButtonStyle-CssClass=”createUser_button”

ContinueButtonStyle-CssClass=”createUser_button”

</div>

</form>

</body>

</html>

The CreateUserWizard control in Listing 26.12 is formatted with Cascading Style Sheets

(see Figure 26.6) The control’s ContinueDestinationPageUrl property is set to the value

”~/Default.aspx” After you successfully register, you are redirected to the

Default.aspx page

NOTE

For the complete list of properties supported by the CreateUserWizard control, see

the Microsoft NET Framework SDK Documentation

Configuring Create User Form Fields

By default, the CreateUserWizard control displays the following form fields:

Username

Password

Confirm Password

Email

Security Question

Security Answer

Tiêu đề	Using The Login Controls
Trường học	University of Wow!
Chuyên ngành	Computer Science
Thể loại	Essay
Năm xuất bản	2025
Thành phố	Wow City

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