- •Table of Contents
- •Preface
- •What is ASP.NET?
- •Installing the Required Software
- •Installing the Web Server
- •Installing Internet Information Services (IIS)
- •Installing Cassini
- •Installing the .NET Framework and the SDK
- •Installing the .NET Framework
- •Installing the SDK
- •Configuring the Web Server
- •Configuring IIS
- •Configuring Cassini
- •Where do I Put my Files?
- •Using localhost
- •Virtual Directories
- •Using Cassini
- •Installing SQL Server 2005 Express Edition
- •Installing SQL Server Management Studio Express
- •Installing Visual Web Developer 2005
- •Writing your First ASP.NET Page
- •Getting Help
- •Summary
- •ASP.NET Basics
- •ASP.NET Page Structure
- •Directives
- •Code Declaration Blocks
- •Comments in VB and C# Code
- •Code Render Blocks
- •ASP.NET Server Controls
- •Server-side Comments
- •Literal Text and HTML Tags
- •View State
- •Working with Directives
- •ASP.NET Languages
- •Visual Basic
- •Summary
- •VB and C# Programming Basics
- •Programming Basics
- •Control Events and Subroutines
- •Page Events
- •Variables and Variable Declaration
- •Arrays
- •Functions
- •Operators
- •Breaking Long Lines of Code
- •Conditional Logic
- •Loops
- •Object Oriented Programming Concepts
- •Objects and Classes
- •Properties
- •Methods
- •Classes
- •Constructors
- •Scope
- •Events
- •Understanding Inheritance
- •Objects In .NET
- •Namespaces
- •Using Code-behind Files
- •Summary
- •Constructing ASP.NET Web Pages
- •Web Forms
- •HTML Server Controls
- •Using the HTML Server Controls
- •Web Server Controls
- •Standard Web Server Controls
- •Label
- •Literal
- •TextBox
- •HiddenField
- •Button
- •ImageButton
- •LinkButton
- •HyperLink
- •CheckBox
- •RadioButton
- •Image
- •ImageMap
- •PlaceHolder
- •Panel
- •List Controls
- •DropDownList
- •ListBox
- •RadioButtonList
- •CheckBoxList
- •BulletedList
- •Advanced Controls
- •Calendar
- •AdRotator
- •TreeView
- •SiteMapPath
- •Menu
- •MultiView
- •Wizard
- •FileUpload
- •Web User Controls
- •Creating a Web User Control
- •Using the Web User Control
- •Master Pages
- •Using Cascading Style Sheets (CSS)
- •Types of Styles and Style Sheets
- •Style Properties
- •The CssClass Property
- •Summary
- •Building Web Applications
- •Introducing the Dorknozzle Project
- •Using Visual Web Developer
- •Meeting the Features
- •The Solution Explorer
- •The Web Forms Designer
- •The Code Editor
- •IntelliSense
- •The Toolbox
- •The Properties Window
- •Executing your Project
- •Using Visual Web Developer’s Built-in Web Server
- •Using IIS
- •Using IIS with Visual Web Developer
- •Core Web Application Features
- •Web.config
- •Global.asax
- •Using Application State
- •Working with User Sessions
- •Using the Cache Object
- •Using Cookies
- •Starting the Dorknozzle Project
- •Preparing the Sitemap
- •Using Themes, Skins, and Styles
- •Creating a New Theme Folder
- •Creating a New Style Sheet
- •Styling Web Server Controls
- •Adding a Skin
- •Applying the Theme
- •Building the Master Page
- •Using the Master Page
- •Extending Dorknozzle
- •Debugging and Error Handling
- •Debugging with Visual Web Developer
- •Other Kinds of Errors
- •Custom Errors
- •Handling Exceptions Locally
- •Summary
- •Using the Validation Controls
- •Enforcing Validation on the Server
- •Using Validation Controls
- •RequiredFieldValidator
- •CompareValidator
- •RangeValidator
- •ValidationSummary
- •RegularExpressionValidator
- •Some Useful Regular Expressions
- •CustomValidator
- •Validation Groups
- •Updating Dorknozzle
- •Summary
- •What is a Database?
- •Creating your First Database
- •Creating a New Database Using Visual Web Developer
- •Creating Database Tables
- •Data Types
- •Column Properties
- •Primary Keys
- •Creating the Employees Table
- •Creating the Remaining Tables
- •Executing SQL Scripts
- •Populating the Data Tables
- •Relational Database Design Concepts
- •Foreign Keys
- •Using Database Diagrams
- •Diagrams and Table Relationships
- •One-to-one Relationships
- •One-to-many Relationships
- •Many-to-many Relationships
- •Summary
- •Speaking SQL
- •Reading Data from a Single Table
- •Using the SELECT Statement
- •Selecting Certain Fields
- •Selecting Unique Data with DISTINCT
- •Row Filtering with WHERE
- •Selecting Ranges of Values with BETWEEN
- •Matching Patterns with LIKE
- •Using the IN Operator
- •Sorting Results Using ORDER BY
- •Limiting the Number of Results with TOP
- •Reading Data from Multiple Tables
- •Subqueries
- •Table Joins
- •Expressions and Operators
- •Transact-SQL Functions
- •Arithmetic Functions
- •String Functions
- •Date and Time Functions
- •Working with Groups of Values
- •The COUNT Function
- •Grouping Records Using GROUP BY
- •Filtering Groups Using HAVING
- •The SUM, AVG, MIN, and MAX Functions
- •Updating Existing Data
- •The INSERT Statement
- •The UPDATE Statement
- •The DELETE Statement
- •Stored Procedures
- •Summary
- •Introducing ADO.NET
- •Importing the SqlClient Namespace
- •Defining the Database Connection
- •Preparing the Command
- •Executing the Command
- •Setting up Database Authentication
- •Reading the Data
- •Using Parameters with Queries
- •Bulletproofing Data Access Code
- •Using the Repeater Control
- •More Data Binding
- •Inserting Records
- •Updating Records
- •Deleting Records
- •Using Stored Procedures
- •Summary
- •DataList Basics
- •Handling DataList Events
- •Editing DataList Items and Using Templates
- •DataList and Visual Web Developer
- •Styling the DataList
- •Summary
- •Using the GridView Control
- •Customizing the GridView Columns
- •Styling the GridView with Templates, Skins, and CSS
- •Selecting Grid Records
- •Using the DetailsView Control
- •Styling the DetailsView
- •GridView and DetailsView Events
- •Entering Edit Mode
- •Using Templates
- •Updating DetailsView Records
- •Summary
- •Advanced Data Access
- •Using Data Source Controls
- •Binding the GridView to a SqlDataSource
- •Binding the DetailsView to a SqlDataSource
- •Displaying Lists in DetailsView
- •More on SqlDataSource
- •Working with Data Sets and Data Tables
- •What is a Data Set Made From?
- •Binding DataSets to Controls
- •Implementing Paging
- •Storing Data Sets in View State
- •Implementing Sorting
- •Filtering Data
- •Updating a Database from a Modified DataSet
- •Summary
- •Security and User Authentication
- •Basic Security Guidelines
- •Securing ASP.NET 2.0 Applications
- •Working with Forms Authentication
- •Authenticating Users
- •Working with Hard-coded User Accounts
- •Configuring Forms Authentication
- •Configuring Forms Authorization
- •Storing Users in Web.config
- •Hashing Passwords
- •Logging Users Out
- •ASP.NET 2.0 Memberships and Roles
- •Creating the Membership Data Structures
- •Using your Database to Store Membership Data
- •Using the ASP.NET Web Site Configuration Tool
- •Creating Users and Roles
- •Changing Password Strength Requirements
- •Securing your Web Application
- •Using the ASP.NET Login Controls
- •Authenticating Users
- •Customizing User Display
- •Summary
- •Working with Files and Email
- •Writing and Reading Text Files
- •Setting Up Security
- •Writing Content to a Text File
- •Reading Content from a Text File
- •Accessing Directories and Directory Information
- •Working with Directory and File Paths
- •Uploading Files
- •Sending Email with ASP.NET
- •Configuring the SMTP Server
- •Sending a Test Email
- •Creating the Company Newsletter Page
- •Summary
- •The WebControl Class
- •Properties
- •Methods
- •Standard Web Controls
- •AdRotator
- •Properties
- •Events
- •BulletedList
- •Properties
- •Events
- •Button
- •Properties
- •Events
- •Calendar
- •Properties
- •Events
- •CheckBox
- •Properties
- •Events
- •CheckBoxList
- •Properties
- •Events
- •DropDownList
- •Properties
- •Events
- •FileUpload
- •Properties
- •Methods
- •HiddenField
- •Properties
- •HyperLink
- •Properties
- •Image
- •Properties
- •ImageButton
- •Properties
- •Events
- •ImageMap
- •Properties
- •Events
- •Label
- •Properties
- •LinkButton
- •Properties
- •Events
- •ListBox
- •Properties
- •Events
- •Literal
- •Properties
- •MultiView
- •Properties
- •Methods
- •Events
- •Panel
- •Properties
- •PlaceHolder
- •Properties
- •RadioButton
- •Properties
- •Events
- •RadioButtonList
- •Properties
- •Events
- •TextBox
- •Properties
- •Events
- •Properties
- •Validation Controls
- •CompareValidator
- •Properties
- •Methods
- •CustomValidator
- •Methods
- •Events
- •RangeValidator
- •Properties
- •Methods
- •RegularExpressionValidator
- •Properties
- •Methods
- •RequiredFieldValidator
- •Properties
- •Methods
- •ValidationSummary
- •Properties
- •Navigation Web Controls
- •SiteMapPath
- •Properties
- •Methods
- •Events
- •Menu
- •Properties
- •Methods
- •Events
- •TreeView
- •Properties
- •Methods
- •Events
- •HTML Server Controls
- •HtmlAnchor Control
- •Properties
- •Events
- •HtmlButton Control
- •Properties
- •Events
- •HtmlForm Control
- •Properties
- •HtmlGeneric Control
- •Properties
- •HtmlImage Control
- •Properties
- •HtmlInputButton Control
- •Properties
- •Events
- •HtmlInputCheckBox Control
- •Properties
- •Events
- •HtmlInputFile Control
- •Properties
- •HtmlInputHidden Control
- •Properties
- •HtmlInputImage Control
- •Properties
- •Events
- •HtmlInputRadioButton Control
- •Properties
- •Events
- •HtmlInputText Control
- •Properties
- •Events
- •HtmlSelect Control
- •Properties
- •Events
- •HtmlTable Control
- •Properties
- •HtmlTableCell Control
- •Properties
- •HtmlTableRow Control
- •Properties
- •HtmlTextArea Control
- •Properties
- •Events
- •Index
Chapter 2: ASP.NET Basics
View State
As we saw briefly in the previous section, ASP.NET controls automatically retain their data when a page is sent to the server in response to an event (such as a user clicking a button). Microsoft calls this persistence of data “view state.” In the past, developers would have had to use hacks to remember the item a user had selected in a drop-down menu, or store the content entered into a text box; typically, these hacks would have relied on hidden form fields.
This is no longer the case: once they’re submitted to the server for processing, ASP.NET pages automatically retain all the information contained in text boxes and drop-down lists, as well as radio button and checkbox selections. They even keep track of dynamically generated tags, controls, and text. Consider the following ASP (not ASP.NET!) page, called Sample.asp:
File: Sample.asp
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>Sample Page using VBScript</title> </head>
<body>
<form method="post" action="sample.asp"> <input type="text" name="nameTextBox"/> <input type="submit" name="submitButton"
value="Click Me" />
<%
If Request.Form("nameTextBox") <> "" Then Response.Write(Request.Form("nameTextBox"))
End If %>
</form>
</body>
</html>
Cassini and ASP
Cassini is an ASP.NET-only web server and will not execute pages written in ASP, such as Sample.asp above. Fortunately, this won’t be a problem as you work your way through this book, as the above Sample.asp file is the only ASP code in this book.
44
View State
If you save this as Sample.asp in the Learning virtual directory you created in Chapter 1, and open it in your browser by entering http://localhost/Learning/Sample.asp, you’ll see that view state is not automatically preserved. When the user submits the form, the information that was typed into the text box is cleared, although it’s still available in Request.Form("nameTextBox"). The equivalent page in ASP.NET, ViewState.aspx, demonstrates this data persistence using view state:
Visual Basic File: ViewState.aspx
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" |
|
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> |
|
<html> |
|
<head> |
|
<title>View State Example</title> |
|
<script runat="server" language="VB"> |
|
Sub Click(s As Object, e As EventArgs) |
|
messageLabel.Text = nameTextBox.Text |
|
End Sub |
|
</script> |
|
</head> |
|
<body> |
|
<form runat="server"> |
|
<asp:TextBox id="nameTextBox" runat="server" /> |
|
<asp:Button id="submitButton" runat="server" |
|
Text="Click Me" OnClick="Click" /> |
|
<asp:Label id="messageLabel" runat="server" /> |
|
</form> |
|
</body> |
|
</html> |
|
C# |
File: ViewState.aspx |
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title>View State Example</title> <script runat="server" language="C#">
void Click(Object s, EventArgs e)
{
messageLabel.Text = nameTextBox.Text;
}
</script>
</head>
<body>
<form runat="server">
45
Chapter 2: ASP.NET Basics
<asp:TextBox id="nameTextBox" runat="server" /> <asp:Button id="submitButton" runat="server"
Text="Click Me" OnClick="Click" /> <asp:Label id="messageLabel" runat="server" />
</form>
</body>
</html>
In this case, the code uses ASP.NET controls with the runat="server" attribute. As you can see in Figure 2.4, the text from the box appears on the page when the button is clicked, but also notice that the data remains in the text box! The data in this example is preserved by view state.
Figure 2.4. ASP.NET maintaining the state of the controls
You can see the benefits of view state already. But where’s all that information stored? ASP.NET pages maintain view state by encrypting the data within a hidden form field. View the source of the page after you’ve submitted the form, and look for the following code:
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/wEPDwUKLTEwNDY1Nzg0MQ9…0fMCR+FN5P6v5pkTQwNEl5xhBk" />
This is a standard HTML hidden form field. All information that’s relevant to the view state of the page is stored within this hidden form field as an encrypted string.
View state is enabled for every page by default. If you do not intend to use view state, you can turn it off, which will result in a slight performance gain in your pages. To do this, set the EnableViewState property of the Page directive to false:
<%@ Page EnableViewState="False" %>
46
Working with Directives
Disabling View State, Control by Control
View state can also be disabled for particular controls in a page: simply set their EnableViewState property to false. We’ll see working examples of this in the following chapters.
Speaking of directives, it’s time to take a closer look at these curious beasts!
Working with Directives
For the most part, ASP.NET pages resemble traditional HTML pages with a few additions. In essence, just using the .aspx extension for an HTML file will ensure that IIS passes the page to the .NET Framework for processing. However, before you can work with certain, more advanced features, you’ll need to know how to use directives.
We talked a little about directives and what they can do earlier in this chapter. You learned that directives control how a page is created, how a page is cached, help with bug-fixing, and allow us to import advanced functionality for use within our code. Three of the most commonly used directives are:
Page
This directive defines page-specific attributes for the ASP.NET page, such as the language used for server-side code. We’ve already seen this directive in use.
Import
The Import directive makes functionality that’s been defined elsewhere available in a given page. The following example, for instance, imports functionality from the System.Web.Mail namespace, which you could use to send email from a page. Namespaces are simply .NET’s way of keeping all its functionality neatly organized—we’ll see how they work in Chapter 3.
<%@ Import Namespace="System.Web.Mail" %>
You’ll become very familiar with this directive as you work through this book.
Register
This directive allows you to register a user control for use on your page. We’ll cover Register in detail in Chapter 4, but the directive looks something like this:
47