- •About the Authors
- •Contents at a Glance
- •Contents
- •Introduction
- •Goal of the Book
- •How to Use this Book
- •Introduction to the .NET Framework
- •Common Language Runtime (CLR)
- •Class Library
- •Assembly
- •Versioning
- •Exceptions
- •Threads
- •Delegates
- •Summary
- •Introduction to C#
- •Variables
- •Initializing Variables
- •Variable Modifiers
- •Variable Data Types
- •Types of Variables
- •Variable Scope
- •Types of Data Type Casting
- •Arrays
- •Strings
- •Initializing Strings
- •Working with Strings
- •Statements and Expressions
- •Types of Statements
- •Expressions
- •Summary
- •Classes
- •Declaring Classes
- •Inheritance
- •Constructors
- •Destructors
- •Methods
- •Declaring a Method
- •Calling a Method
- •Passing Parameters to Methods
- •Method Modifiers
- •Overloading a Method
- •Namespaces
- •Declaring Namespaces
- •Aliases
- •Structs
- •Enumerations
- •Interfaces
- •Writing, Compiling, and Executing
- •Writing a C# Program
- •Compiling a C# Program
- •Executing a C# Program
- •Summary
- •Arrays
- •Single-Dimensional Arrays
- •Multidimensional Arrays
- •Methods in Arrays
- •Collections
- •Creating Collections
- •Working with Collections
- •Indexers
- •Boxing and Unboxing
- •Preprocessor Directives
- •Summary
- •Attributes
- •Declaring Attributes
- •Attribute Class
- •Attribute Parameters
- •Default Attributes
- •Properties
- •Declaring Properties
- •Accessors
- •Types of Properties
- •Summary
- •Introduction to Threads
- •Creating Threads
- •Aborting Threads
- •Joining Threads
- •Suspending Threads
- •Making Threads Sleep
- •Thread States
- •Thread Priorities
- •Synchronization
- •Summary
- •Case Study
- •Project Life Cycle
- •Analyzing Requirements
- •High-Level Design
- •Primary and Foreign Keys
- •Referential Integrity
- •Normalization
- •Designing a Database
- •Low-Level Design
- •Construction
- •Integration and Testing
- •User Acceptance Testing
- •Implementation
- •Operations and Maintenance
- •Summary
- •Creating a New Project
- •Console Application
- •Windows Applications
- •Creating a Windows Application for the Customer Maintenance Project
- •Creating an Interface for Form1
- •Creating an Interface for WorkerForm
- •Creating an Interface for CustomerForm
- •Creating an Interface for ReportsForm
- •Creating an Interface for JobDetailsForm
- •Summary
- •Performing Validations
- •Identifying the Validation Mechanism
- •Using the ErrorProvider Control
- •Handling Exceptions
- •Using the try and catch Statements
- •Using the Debug and Trace Classes
- •Using the Debugging Features of Visual Studio .NET
- •Using the Task List
- •Summary
- •Creating Form1
- •Connecting WorkerForm to the Workers Table
- •Connecting CustomerForm to the tblCustomer Table
- •Connecting the JobDetails Form
- •to the tblJobDetails Table
- •Summary
- •Introduction to the Crystal Reports Designer Tool
- •Creating the Reports Form
- •Creating Crystal Reports
- •Creating the Windows Forms Viewer Control
- •Creating the Monthly Worker Report
- •Summary
- •Introduction to Deploying a Windows Application
- •Deployment Projects Available in Visual Studio .NET
- •Deployment Project Editors
- •Summary
- •Case Study
- •Project Life Cycle
- •Analyzing Requirements
- •High-Level Design
- •Low-Level Design
- •Summary
- •Populating the TreeView Control
- •Displaying Employee Codes in the TreeView Control
- •Event Handling
- •Displaying Employee Details in the ListView Control
- •Summary
- •Case Study
- •Project Life Cycle
- •Analyzing Requirements
- •High-Level Design
- •Low-Level Design
- •Summary
- •Adding the Programming Logic to the Application
- •Adding Code to the Form Load() Method
- •Adding Code to the OK Button
- •Adding Code to the Exit Button
- •Summary
- •The Created Event
- •Adding Code to the Created Event
- •Overview of XML
- •The XmlReader Class
- •The XmlWriter Class
- •Displaying Data in an XML Document
- •Displaying an Error Message in the Event Log
- •Displaying Event Entries from Event Viewer
- •Displaying Data from the Summary.xml Document in a Message Box
- •Summary
- •Airline Profile
- •Role of a Business Manager
- •Role of a Network Administrator
- •Role of a Line-of-Business Executive
- •Project Requirements
- •Creation and Deletion of User Accounts
- •Addition of Flight Details
- •Reservations
- •Cancellations
- •Query of Status
- •Confirmation of Tickets
- •Creation of Reports
- •Launch of Frequent Flier Programs
- •Summarizing the Tasks
- •Project Design
- •Database Design
- •Web Forms Design
- •Enabling Security with the Directory Structure
- •Summary
- •Getting Started with ASP.NET
- •Prerequisites for ASP.NET Applications
- •New Features in ASP.NET
- •Types of ASP.NET Applications
- •Exploring ASP.NET Web Applications
- •Introducing Web Forms
- •Web Form Server Controls
- •Configuring ASP.NET Applications
- •Configuring Security for ASP.NET Applications
- •Deploying ASP.NET Applications
- •Creating a Sample ASP.NET Application
- •Creating a New Project
- •Adding Controls to the Project
- •Coding the Application
- •Summary
- •Creating the Database Schema
- •Creating Database Tables
- •Managing Primary Keys and Relationships
- •Viewing the Database Schema
- •Designing Application Forms
- •Standardizing the Interface of the Application
- •Common Forms in the Application
- •Forms for Network Administrators
- •Forms for Business Managers
- •Forms for Line-of-Business Executives
- •Summary
- •The Default.aspx Form
- •The Logoff.aspx Form
- •The ManageUsers.aspx Form
- •The ManageDatabases.aspx Form
- •The ChangePassword.aspx Form
- •Restricting Access to Web Forms
- •The AddFl.aspx Form
- •The RequestID.aspx Form
- •The Reports.aspx Form
- •The FreqFl.aspx Form
- •Coding the Forms for LOB Executives
- •The CreateRes.aspx Form
- •The CancelRes.aspx Form
- •The QueryStat.aspx Form
- •The ConfirmRes.aspx Form
- •Summary
- •Designing the Form
- •The View New Flights Option
- •The View Ticket Status Option
- •The View Flight Status Option
- •The Confirm Reservation Option
- •Testing the Application
- •Summary
- •Locating Errors in Programs
- •Watch Window
- •Locals Window
- •Call Stack Window
- •Autos Window
- •Command Window
- •Testing the Application
- •Summary
- •Managing the Databases
- •Backing Up the SkyShark Airlines Databases
- •Exporting Data from Databases
- •Examining Database Logs
- •Scheduling Database Maintenance Tasks
- •Managing Internet Information Server
- •Configuring IIS Error Pages
- •Managing Web Server Log Files
- •Summary
- •Authentication Mechanisms
- •Securing a Web Site with IIS and ASP.NET
- •Configuring IIS Authentication
- •Configuring Authentication in ASP.NET
- •Securing SQL Server
- •Summary
- •Deployment Scenarios
- •Deployment Editors
- •Creating a Deployment Project
- •Adding the Output of SkySharkDeploy to the Deployment Project
- •Deploying the Project to a Web Server on Another Computer
- •Summary
- •Organization Profile
- •Project Requirements
- •Querying for Information about All Books
- •Querying for Information about Books Based on Criteria
- •Ordering a Book on the Web Site
- •Project Design
- •Database Design
- •Database Schema
- •Web Forms Design
- •Flowcharts for the Web Forms Modules
- •Summary
- •Introduction to ASP.NET Web Services
- •Web Service Architecture
- •Working of a Web Service
- •Technologies Used in Web Services
- •XML in a Web Service
- •WSDL in a Web Service
- •SOAP in a Web Service
- •UDDI in a Web Service
- •Web Services in the .NET Framework
- •The Default Code Generated for a Web Service
- •Testing the SampleWebService Web Service
- •Summary
- •Creating the SearchAll() Web Method
- •Creating the SrchISBN() Web Method
- •Creating the AcceptDetails() Web Method
- •Creating the GenerateOrder() Web Method
- •Testing the Web Service
- •Securing a Web Service
- •Summary
- •Creating the Web Forms for the Bookers Paradise Web Site
- •Adding Code to the Web Forms
- •Summary
- •Case Study
- •Project Life Cycle
- •Analyzing Requirements
- •High-Level Design
- •Low-Level Design
- •Summary
- •Overview of Mobile Applications
- •The Microsoft Mobile Internet Toolkit
- •Overview of WAP
- •The WAP Architecture
- •Overview of WML
- •The Mobile Web Form
- •The Design of the MobileTimeRetriever Application
- •Creating the Interface for the Mobile Web Forms
- •Adding Code to the MobileTimeRetriever Application
- •Summary
- •Creating the Forms Required for the MobileCallStatus Application
- •Creating the frmLogon Form
- •Creating the frmSelectOption Form
- •Creating the frmPending Form
- •Creating the frmUnattended Form
- •Adding Code to the Submit Button in the frmLogon Form
- •Adding Code to the Query Button in the frmSelectOption Form
- •Adding Code to the Mark checked as complete Button in the frmPending Form
- •Adding Code to the Back Button in the frmPending Form
- •Adding Code to the Accept checked call(s) Button in the frmUnattended Form
- •Adding Code to the Back Button in the frmUnattended Form
- •Summary
- •What Is COM?
- •Windows DNA
- •Microsoft Transaction Server (MTS)
- •.NET Interoperability
- •COM Interoperability
- •Messaging
- •Benefits of Message Queues
- •Limitations
- •Key Messaging Terms
- •Summary
- •Pointers
- •Declaring Pointers
- •Types of Code
- •Implementing Pointers
- •Using Pointers with Managed Code
- •Working with Pointers
- •Compiling Unsafe Code
- •Summary
- •Introduction to the Languages of Visual Studio .NET
- •Visual C# .NET
- •Visual Basic .NET
- •Visual C++ .NET
- •Overview of Visual Basic .NET
- •Abstraction
- •Encapsulation
- •Inheritance
- •Polymorphism
- •Components of Visual Basic .NET
- •Variables
- •Constants
- •Operators
- •Arrays
- •Collections
- •Procedures
- •Arguments
- •Functions
- •Adding Code to the Submit Button
- •Adding Code to the Exit Button
- •Summary
- •Introduction to Visual Studio .NET IDE
- •Menu Bar
- •Toolbars
- •Visual Studio .NET IDE Windows
- •Toolbox
- •The Task List Window
- •Managing Windows
- •Customizing Visual Studio .NET IDE
- •The Options Dialog Box
- •The Customize Dialog Box
- •Summary
- •Index
732 Project 6 CREATING A MOBILE APPLICATION
I will discuss how to create a mobile Web application by using the Mobile Web Application project type later in this chapter. I will first discuss the transfer protocol used with the mobile applications that can be accessed from a mobile phone, WAP. However, when you access the mobile application from a PDA, the transfer protocol used will be TCP/IP.
Overview of WAP
I have already discussed the limitations of the earlier mobile Web applications, such as low memory and CPU capacity and higher bandwidth requirements. As a solution to these problems, a new protocol was developed. This protocol enables a wireless device, such as a mobile phone or a two-way pager, to access a Web site on the Internet. Therefore, this protocol was named WAP. WAP is a communication protocol, or a set of rules, that allows a wireless device to access a mobile application. To enable a user to access a mobile application, the user needs to have a WAP-enabled mobile device, such as a WAP-enabled mobile phone.
WAP is an industry standard developed by the WAP Forum that provides a set of rules for communication between the wireless devices and the world of the Internet. In addition, it provides telephony services for several wireless devices. WAP extends support to several advanced Internet technologies, such as IP (Internet Protocol ), TCP (Transmission Control Protocol ), and HTTP (Hypertext Transfer Protocol ).This makes it possible for a wireless device to utilize the functionality of these Internet technologies.
In addition, the wireless devices have hardware factors suitable for accessing an Internet site from the device. These hardware factors include a small screen, limited RAM, ROM, and a battery. These devices also allow users to navigate through the site by using the one-finger navigation feature, which makes navigation fun for the users.The wireless devices are capable of using the maximum
THE WAP FORUM
WAP is a protocol developed by the WAP Forum. The WAP Forum works in coordination with several organizations, such as W3C (World Wide Web Consortium), to provide the wireless industry with a global specification for all wireless networks. In this context, the WAP Forum released its first specification, WAP 1.0, in 1998.The WAP Forum has also released its second specification, WAP 2.0. The WAP Forum includes the major wireless technology companies, such as Nokia, Ericsson, Oracle Corporation, and so on.
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power of processors, which reduces the overall cost of accessing the application from a wireless device.
To access an Internet site from a mobile device, your mobile device needs to be WAP-enabled. A WAP-enabled mobile device has microbrowser software installed on it.This software is used to send and receive a user’s request for accessing a Web site. For example, when a user tries to access a site from the WAPenabled device, the microbrowser sof tware sends a request to the server to allow the user to access the site. The following section discusses the WAP architecture in detail.
The WAP Architecture
To understand the concept of the WAP architecture, first have a look at the Web architecture.The Web architecture refers to the architecture involved when a user tries to access a Web site from a Web browser. When a user tries to access a Web site on a Web server, a request for the site is sent from the client to the server. In this case, the client is the Web browser that sends a URL (Uniform Resource Locator) request to the server, which is the Web server. Then, at the server site, the request is processed in the form of CGI (Common Gateway Interface) scripts, and the content of the site is returned to the client as a response to the user’s request. Figure 32-3 shows the Web architecture in detail.
FIGURE 32-3 The Web architecture
734 Project 6 CREATING A MOBILE APPLICATION
After learning about the Web architecture, you can easily understand the WAP architecture.The WAP architecture is similar to the Web architecture, except that the WAP architecture involves a WAP gateway that acts as an interface between the client and the server. A WAP gateway is software placed between the client and the ser ver that supports the WAP standards and the Internet protocols, such as HTTP and IP. In addition, the WAP gateway supports XML (Extensible Markup Language) and WML. A WAP gateway consists of encoders, decoders, and script compilers that are used for communication between the client and the server.
In the case of a mobile device trying to access an Internet site, the mobile device becomes the client and the Web ser ver is the server from where the site is being accessed. Figure 32-4 shows the WAP architecture in detail.
FIGURE 32-4 The WAP architecture
As you can see in the figure, to access a Web site from a client (mobile device), the client first needs to send a request for the site. To do this, the client establishes a connection to the WAP gateway. Once a connection is established, the WAP gateway software uses an encoder to encode or convert the request to a form that is easily understood by the Internet server. This encoded form of the request is then forwarded to the server where the request is further processed.
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TIP
WAP allows users to access only WAP-enabled sites, such as www.google.com and www.yahoo.com.
Then, as a response to the user’s request, the server sends the content of the site to the client. However, a user of a mobile device cannot read this content in the form returned by the server. Therefore, the WAP gateway transfers the content in the Internet language to a form supported by WAP devices, such as WML and WMLScript. WAP uses the WML and WMLScript languages to send and receive data on a wireless device. The data is then displayed to the user by using the microbrowser software on the mobile device.
Overview of WML
WML is a language based on XML. In addition to releasing specifications on WAP, the WAP Forum releases specifications on WML. Similar to XML, WML provides a standard for describing data.The standards defined for describing data are based on the W3C standards. You have learned about XML in detail in Chapter 17, “Interacting with a Microsoft Word Document and Event Viewer,” in the section “Overview of XML.”
The standards defined for describing data in WML are stored as rules in a document called DTD (Document Type Definition). This implies that the DTD document stores the syntax for describing data in a WML document. In addition, a DTD document can include the definition of the elements to be used in the WML document. The elements in a WML document are enclosed within tags. WML allows the users to define the tags to be used in the WML documents. While describing data in a WML document, you need to associate your WML document to a DTD document.
I have already discussed the use of the microbrowser software. A microbrowser understands and fully supports the syntax of a WML document.
After discussing the technology and the transfer protocol for a mobile Web application, I will discuss a simple mobile Web application. The following section discusses the mobile Web application that includes a mobile Web form.
736 Project 6 CREATING A MOBILE APPLICATION
Creating a Simple Mobile Web
Application by Using the Mobile
Internet Toolkit
As discussed earlier, when you install the Mobile Internet Toolkit on your computer, the Mobile Web Application project type is added to the New Project dialog box. You can use this project type option to create a sample mobile Web application. To access the mobile Web application project type, perform the following steps:
1.On the File menu, point to the New option.
2.In the displayed list, click on the Project option. The New Project dialog box is displayed.
3.In the Project Types: pane of the New Project dialog box, select the Visual C# option.
4.In the Templates: pane, select the Mobile Web Application option.
5.In the Location: text box, the localhost appears by default. Type the name of the application as MobileTimeRetriever.
Figure 32-5 shows the New Project dialog box.
6.Click on the OK button.
FIGURE 32-5 The New Project dialog box for the MobileTimeRetriever application