Week 7: Introduction to serverside scripting

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Week 7 Introduction to server-side scripting

• How a server side page works?
• -   Basically, A Web requires two components a
  Web server and a client
• -   The client is usually a browser (I.E/Netscape
  etc)
• -   Both the server the client can communicate
  each other.
• -   Must use a defined protocol to communicate
• -   The most common protocols are HTTP FTP and
  also carried over an underlying network protocol
  called TCP/IP
• -   The client sends an initialization (is a
  defined series of bytes) to start a session, when
  the server receives the initialization request,
  it acknowledges the transmission by returning
  another series of bytes to the client.
• -   The conversation between client server
  continues in this back-and forth manner.

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Week 7 Introduction to server-side scripting

• -  You can imagine the conversation being
  conducted as follows
• Client Hello?
• Server Hello. I speak English.
• Client I speak English too.
• Server What do you want?
• Client I want the file /mySite/myFiles/file1.htm
• Server Heres some information about that file
• Client Thanks, please send the data
• Server Starting data transmission
• Client I got packet 1. Send packet 2.
• Server Sending packet 2.
• ----------
• Server All packets sent.
• Client All packets received in good condition.
  Goodbye!
• Server Goodbye!.

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Week 7 Introduction to server-side scripting

• 1 What is ASP
• -   Stands for Active Server Pages
• -   An ASP is a Web page that is processed by a
  web server
• -   ASP is a Microsoft technology
• -   ASP is a program that runs inside a web
  server (IIS/PWS)
• -   IIS is Internet Information Services comes as
  a free component with windows 2000 windows NT
  4.0 option pack
• -   PWS is Personal Web Page, a smaller scale
  version but fully function like IIS
• -   ChileASP/InstantASP is a technology that runs
  ASP without Windows OS
• -   An ASP file can contain text, HTML, XML and
  scripts. The file extension- .asp
• -   Scripts in an ASP file are executed on the
  server.

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Week 7 Introduction to server-side scripting

• 2. Working with IIS/PWS and ASP
• -   You can choose either IIS/PWS as a web server
  to run your ASP file
• -   If you choose IIS, you must have access to a
  Windows NT 4.0 server with IIS 4.0 or Windows
  2000 Server with IIS 5.0.
• -   Or you can install PWS on your local hard
  disk and enables you to work as same as ISS.
• -   PWS/IIS designate a master directory on the
  hard drive that contains all date and script file
  for use by Internet Server.
• -   The default master directory is \InetPub
• -   You can place your ASP file under
  subdirectory \wwwroot (Example
  C\InetPub\wwwroot\MyFirstAsp.asp)
• -   IIS/PWS have built-in intelligence that knows
  to route a request for a Web page using HTTP to
  this directory.

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Week 7 Introduction to server-side scripting

• JavaScripts (Jscript) vs. VBScript
• -   By default, ASP using VBScript because ASP is
  Microsoft technology
• -   But we can choose other languages like
  JavaScript or JScript by specifying the language
  like lt _at_Language JavaScript gt
• -   JavaScript is Netscapes cross platform which
  is used originally as a scripting language for
  Netscape browser.
• -   Basically, Jscript is the same thing but
  often used by Microsoft.
• -   Most of the resources about ASP use the
  VBScript scripting language and JavaScript most
  popular on the client side scripting language.

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Week 7 Introduction to server-side scripting

• -  
• We use JavaScript on the ASP for a number of
  reasons
• o       JavaScript is an open protocol. VBScript
  is not
• o       JavaScript is case-sensitive, where
  VBScript is not.
• o       JavaScript is larger and more complex
  language than VBScript.
• o       JavaScript is more aware of HTML than
  VBScript and has numerous
• formatting and parsing methods for
  creating and analyzing HTML tags.
• o       JavaScript is, in some ways, more
  powerful than VBScript. VBScript
• version 5 has almost closed the gap.
•  

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Week 7 Introduction to server-side scripting

• Basic ASP scripting style
• -Server side scripting is a script that is
  executed by the web server, then the results of
  which are passed on to the calling client.
• -It begins with lt _at_LANGUAGE JAVASCRIPT gt
  (this is for JavaScript)
• -So, we must put tag lt . gt and start
  writing code in between the tags.
• - Example 1.5_my_first.asp

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Week 7 Introduction to server-side scripting

• lt_at_LANGUAGE"JAVASCRIPT"gt
• lthtmlgt
• ltheadgt
• lttitlegtMy First ASPlt/titlegt
• lt/headgt
• ltbodygt
• lt
• Response.Write("This is my first ASP")
• gt
• lt/bodygt
• lt/htmlgt

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Week 7 Introduction to server-side scripting

• -       Style of writing scripts
• 1. Writing Inline Script  
• -Means that the server-side scripting engine in
  the order that it appears in the ASP page
  executes the script.
• -You can indicate inline server-side script in
  your page by placing the programming statements
  between the following tags lt gt.
• Example 1.5_inline.asp

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Week 7 Introduction to server-side scripting

• lt_at_LANGUAGE"JAVASCRIPT"gt
• lthtmlgt
• ltheadgt
• lttitlegtMy First ASPlt/titlegt
• lt/headgt
• ltbodygt
• lt
• var now new Date()
• Response.Write("This is my first ASPltbrgt")
• Response.Write(now)
• gt
• lt/bodygt
• lt/htmlgt

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Week 7 Introduction to server-side scripting

• 2. Interspersing Inline Script
• -You can intersperse inline script within an ASP.
• -The script is executed in the order in which it
  is encountered
• -Example 1.5_intersperse.asp

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Week 7 Introduction to server-side scripting

• lt_at_LANGUAGE"JAVASCRIPT"gt
• lthtmlgt
• ltheadgtlttitlegtMy First ASPlt/titlegtlt/headgt
• ltbodygt
• lt
• var now new Date()
• Response.Write("ltBgt" "This is my second
  ASP" "lt/Bgt" "ltbrgt")
• Response.Write(now.toString() "ltBRgt")
• gt
• lt
• now.setDate(now.getDate()-1)
• Response.Write("This was my first
  ASPltbrgt")
• Response.Write(now.toString())
• gt lt/bodygt lt/htmlgt