ASP.NET Architecture and Configuration

Page Architecture

• ASP.NET utilizes a client-server architecture.
• The browser submits a request for a page.
• The server processes the request.
• The server returns an HTML response.
• Presentation Layer (UI Layer) consists of ASPX pages that display data.
• Business Logic Layer (BLL) processes data and includes core logic.
• Data Access Layer (DAL) manages DB connections using ADO.NET.
• Database Layer is responsible for storing and retrieving information.

Types of Extensions

• ASP.NET uses various file extensions.
• ".aspx" indicates a Web Page.
• ".ascx" indicates a User Control.
• ".config" indicates a Configuration File.
• ".cs" or ".vb" indicate Code Files.
• ".dll" indicates a Dynamic Link Library.

Web.config File

• Web.config is an XML-based file for application configuration settings.
• It stores database connections, authentication settings, and error handling settings.
• It applies only to specific applications.

Global.asax File

• Handles application-level events like Application_Start and Session_Start.
• Useful for logging, error handling, and session tracking.

Connected & Disconnected Architecture

• Connected Architecture employs SqlDataReader for fast, forward-only database access.
• Disconnected Architecture utilizes DataSet to store data temporarily.

GridView Control

• Displays data in a tabular format, featuring sorting, paging, and editing capabilities.

ListBox & ComboBox

• ListBox allows multiple selections.
• ComboBox allows a single selection.

User Control Steps

• Create a .ascx file.
• Incorporate controls and logic.
• Register the User Control on the ASPX page.

Deployment in IIS

• Open IIS Manager.
• Create a new website.
• Choose the website folder.
• Assign a Port (e.g., 8080).
• Start the website.

DataReader

• Reads data row by row with fast, forward-only access.

Dataset

• Stores multiple tables in memory in disconnected mode.

Types of Caching

• Output Caching caches the entire page output.
• Data Caching caches data retrieved from the database.
• Application Caching stores reusable data.

Cache Expiration Policies

• Absolute Expiration expires at a specific time.
• Sliding Expiration resets expiration on each access.

ADO.NET Architecture

• Key components include Connection, Command, DataReader, DataAdapter, and Dataset.

Master Page

• Provides a consistent layout across multiple pages.

DataTable

• Represents a single table in memory.

Tracing

• Helps debug ASP.NET execution details.

ASP.NET Page Life Cycle Stages

• Request
• Initialization
• Load
• PostBack Handling
• Render

Full Forms

• IIS: Internet Information Services
• CLR: Common Language Runtime
• ADO.NET: ActiveX Data Objects for .NET

Definitions

• Session: Temporary user data storage.
• Cookies: Small text files in browser.

Authentication & Authorization

• Authentication confirms your identity.
• Authorization confirms your access privileges.

Key ASP.NET Questions and Answers

• System.Data namespace is used to create DataTable and DataSet objects.
• .aspx , .ascx are two extensions used in ASP.NET.
• Open(), Close() are two methods of Connection Class.
• ASP stands for Active Server Pages.
• .config is used for ASP.NET Configuration files.
• SOAP stands for Simple Object Access Protocol.
• ViewState property preserves ASP.NET control values when a page posts to itself.
• <%@ Page Language="C#" %> provides metadata about the ASP.NET page.
• TextBox has TextMode property.
• WSDL stands for Web Services Description Language.
• DLL files store reusable code in .NET applications.
• CLR stands for Common Language Runtime.
• IIS stands for Internet Information Services.
• Authentication Modes include: Windows, Forms, Passport, and Custom.
• Controls with ListItem attributes: DropDownList, ListBox
• ADO stands for ActiveX Data Objects.
• ExecuteReader(), ExecuteNonQuery() are two methods in Command Class.
• Caching types: Output Caching, Data Caching.
• Custom Validation Control allows user-defined validation logic.
• ControlToValidate, ErrorMessage are two properties of RequiredFieldValidator Control.

DataTable and Dataset Objects

• System.Data namespace is used to create DataTable and DataSet objects in ADO.NET.
• DataTable is a single table that stores data in rows and columns. It is part of System.Data namespace in ADO.NET.
• Dataset is a collection of multiple DataTable objects and is used for storing relational data in memory.

Other Controls

• The Calendar control in ASP.NET allows users to select dates and are useful for date selection in forms.
• The TextBox control allows users to enter input text.
• The ListBox control enables users to select multiple items.

Connection Class

• The SqlConnection class is used to establish a connection to an SQL database.

IIS Installation Steps

• Open Control Panel > Programs > Turn Windows features on or off.
• Select Internet Information Services (IIS) and click OK.
• Open Run and type inetmgr to launch IIS.

Custom Error Handling

• Custom error handling is done using Web.config.

Web.Config File

• Used in ASP.NET applications to store settings like database connections, authentication, and error handling.

Tracing in ASP.NET

• Tracing in ASP.NET monitors web page / application execution and AIDS developers with debugging information.
• To enable application-level tracing: <trace enabled="true" requestLimit="10" pageOutput="true"/>, add it to Web.config.

2 Key Validation Controls

• RequiredFieldValidator ensures a field isn't left empty.
• RegularExpressionValidator ensures input matches a specific pattern (e.g., email).

Page Directive + Attributes

• <%@ Page %> directive defines settings + properties of an ASP.NET page.
• Common Attributes:
  • Language = specifies the programming language.
  • AutoEventWireup = enables automated event handling.
  • CodeBehind = links to the code file.

ViewState in ASP.NET

• ViewState preserves data between postbacks:
  • Ex: ViewState["UserName"] = "John";
  • Then Ex: string userName = ViewState["UserName"].ToString();

QueryString in ASP.NET

• A QueryString passes data between pages using a URL:
  • SendingData: Response.Redirect("NextPage.aspx?name=John");
  • Receiving Data: string name = Request.QueryString["name"];

Ad Rotator control

• ASP.NET's AdRotator control rotates advertisements, selecting them from a configured XML file.

SOAP

• SOAP exchanges structured information in web services, uses XML-based messaging, and HTTP, SMTP, (more) protocols.

ADO.NET Architecture

• Connects to the database using Connection Object (SqlConnection)
• Executes SQL queries with Command Object (SqlCommand).
• Reads data forwards-only, through DataReader (SqlDataReader).
• Functions as database + DataSet bridge through DataAdapter (SqlDataAdapter).
• Stores multiple tables in memory through DataSet.