Skip to main content

ASP.NET Basics


ASP.NET is a server side technology for developing web based applications based on Microsoft .Net  Framework. ASP.NET is run on the web server. When a user click on a page/website link on a web browser, a request is sent to the web server. The web server reads the code and generates a web page . The web page is then sent to the browser where the client reads this page. Since the processing is on the server, it is called 'Server Side technology'.

Features of ASP.NET:
  1. It lets you write server side code using over 40 languages. Most popular being C# and VB
  2. ASP.NET pages are compiled, not interpreted
  3. It has full access to the functionality  of .Net Framework... XML, web services, database interaction, emails, regular expression
  4. You can separate server side code of your page from HTML layout
  5. Easy to reuse common User Interface elements

An ASP.NET page generally consists of the following:
1. Directive: Controls how page is compiles , how page is cached by web browser, error fixing, import classes. It start with <%@, followed by directive name, attribute,value and ends with %
example: 
<%@ Page Languauge = "VB" %> 
<% Import Namespace = "System.Web.Mail" %>
<% Register TagPrefix = "xx" TagName = "name", src = "footer.ascx">    // to register a user control
2. Code declaration block: Contains all application logic between <script>   </script> tags
eg: <script language = "VB" runat = "server">          
// code here
</script>
3. Code Render block: defines inline code or expression that will execute when page will render
<% Dim title as string = "example" %>
<%= title %>
4. ASP.NET server controls
5. Server Side comments. These are different from client side comments, as they do not get displayed in the client code
6. literal text and HTML tags

In short, ASP.NET pages are simply text files that have .aspx file extension. When a client requests a ASP.NET page, the web server passes the page to ASP.NET runtime. ASP.NET runtime reads the page and compiles it into .NET class. This class is then used to produce HTML that is sent back to the user. Each new request to the same page, need not go through all the steps and can respond directly.

Comments

Popular posts from this blog

Insufficient access rights to perform the operation. (Exception from HRESULT: 0x80072098)

While accessing the active directory (AD) and authorization manager (AZMAN) , If you get “   Insufficient access rights to perform the operation. (Exception from HRESULT: 0x80072098)  “ message check the    account that is being used to get the LDAP query from AD .  ERROR DETAILS Exception Details:  System.Runtime.InteropServices.COMException: Insufficient access rights to perform the operation. (Exception from HRESULT: 0x80072098) Source Error: Line 154:    'Session("FullName") = System.Security.Principal.WindowsIdentity.GetCurrent.Name.ToString() Line 155: Line 156:    If Not User.IsInRole("Role1") Then Line 157:          Response.Redirect("./Login.aspx") Line 158:    End If  Stack Trace : .... SOLVE IT Steps to do check the app pool rights: Click on the website name that you are having problem with in IIS  In the right panel you will se...

Do's and Don't SQL

Do's: Writing comments whenever something is not very obvious, as it won’t impact the performance.  (--) for single line  (/*…*/) to mark a section Use proper indentation Use Upper Case for all SQL keywords. SELECT, UPDATE, INSERT, WHERE, INNER JOIN, AND, OR, LIKE. Use BEGIN... END block for multiple statements in conditional code  Use Declare and Set in beginning of Stored procedure Create objects in same database where its relevant table exists otherwise it will reduce network performance. Use PRIMARY key in WHERE condition of UPDATE or DELETE statements as this will avoid error possibilities. If User table references Employee table than the column name used in reference should be UserID where User is table name and ID primary column of User table and UserID is reference column of Employee table. Use select column name instead of select * Use CTE (Common Table Expression); its scope is limited to the next statement in SQL query, instead of...

SQL Server 2008 - Inline Variable Assignment

Microsoft SQL Server 2008 brings in a new feature of 'Declaring and Assigning' a variable all in a single line. Earlier, while using SQL 2005 and earlier versions, we had to declare a variable before assigning it. This feature is explained in detail below. In SQL 2005 and earlier versions we had to write: Declare @age int Declare @name nvarchar(25) Declare @date date Set @age = 25 Set @name = "Garry" Set @date = GETDATE() With SQL 2008 we can combine both these statements to write Declare @age int = 25 Declare @name nvarchar(25) Declare @date @date = GETDATE() Advantage : This helps us to write less code, yet get the same functionality. Even though this feature has been available it is not being used in many projects because of backward compatibility issue. If the same code is being used on both 2005 and 2008 server we would prefer writing in a format compatible to both. Do share with us :  Would you like to use this new method? If not, why?