Active Server Pages ASPs are Web pages ASP

Active Server Pages (ASPs) are Web pages ASP = server-side scripts + HTML The appearance of an Active Server Page depends on who or what is viewing it. • If the Web browser that receives it, an Active Server Page looks just like a normal HTML page. • However, the file located in the server looks very different. In addition to text and HTML tags, you also see server-side scripts. This is what the Active Server Page looks like to the Web server before it is processed and sent in response to a request. 1

How ASP Works? 1. User brings up a Web site where the default page has the extension. asp. 2. The browser requests the ASP file from the Web server 3. The server-side scripts begins to run with ASP. 4. ASP processes the requested file sequentially (top-down), executes any script command contained in the file, and produces an HTML Web page. 5. The Web page is sent to the browser. 2

ASP vs HTML ASP = HTML + some other stuff! What is the difference? Basically we are taking the HTML and adding some elements. . . • ASP files end with the. asp extension, so the Web server knows what it is. • ASP files include server-side code that contain instructions for the server. • Browser can not display your code! • ASP files provide dynamic information 3

Active Server Pages Server-side scripts ~ HTML tags. <%. . . %> ~ <. . . > You can insert server-side scripts anywhere in your Web page-even inside HTML tags. <h 1> <% = “Hello World” %> </h 1> The server looks inside the ASP tags and runs the instructions, sends the results 4

Vbscript - Scripting Language • Default Language of ASP Vb. Script <% @ language = Vb. Script %> (no need to write!) • ASP Java. Script <% @ language = Javascript %> • General Syntax: <% object. method “parameter 1”, “parameter 2” %> <% response. write “print this out!. . ” %> 5

ASP Objects 1. 2. 3. 4. 5. Request object, Response object, Server object, Session object, Application Object. It connects, or relates, these objects to Active. X Data Objects (ADO) • Connection object, • Recordset object, • Command Objects. 6

ASP – Request Object • gets information from client browsers • submits it to the Web server <input name = “Email”> <% =request. form(“Email”)%> It provides the following basic data collection functions; Ø Form (collects data from fill-in forms by using post method) Ø Query. String (same; but the method is get. Appends data to the URL given in the Action attribute of a form) Ø Server. Variables (generates HTTP and server information about a visitor’s site) Ø Cookies (stored as small text files on client computers retrieved by the Web server each time the client browser opened. ) 7

Examples – Request Object <% for each SV in Request. Server. Variables response. write "" & SV & " = " & Request. Server. Variables(SV) & "" next %> <% for each item in Request. Cookies response. write "" & Cookie & "=" & Request. Cookies(item) & "" next %> 8

ASP – Response Object • takes information from Web server • sends to the client browsers • redirects the browser to the different URL • sends cookies to the browser Examples; <% Response. Write “Hello World. ” %> <% Response. Redirect (“page. htm”) %> 9

ASP-Server Object • Sets the maximum amount of time a script can run before it times out • Takes a string and either HTML or URL encode it • Converts a virtual web address to an absolute path on the server <% set connection = Server. Create. Object(“ADODB. Connection”) %> 10

ASP-Session Object The process of a Web user’s visit through the pages is called a session. • Used to identify users of the application • Useful for site counters and for login <% Session(“loggedin”) = “yes”%> The Web server automatically creates the Session object. 11

ASP-Application Object Used to store and share information that can be used on the entire application. To store Web address; <% Application(“Homepage”) = “http: //www. bim. bilkent. edu. tr/~ikinci %> <a href = “<% = Application(“homepage”) %>”>Home Page </a> To store the database connection string; <% conn 341 = “DRIVER = {Microsoft Access Driver (*. mdb)}; ” conn 341 = conn 341 & “DBQ =“ & Server. Map. Path(“dbase/db 341. mdb”) Application(“connection”) = conn 341 %> <% Set conn = Server. Create. Object(“ADODB. Connection”) Conn. Open Application(“connection”) %> 12

ADO - Active. X Data Objects ADOs provide a mechanism for the Web-based client/server application to access various databases. ADOs are designed to interface with the relational databases through the Open Database Connectivity (ODBC). ADO includes 3 objects; Ø Connection object, Ø Recordset object, Ø Command object. 13

ASP and ADO Object Model Structure Web server Server object Request object Client Browser Response object Data server Active. X data object (ADO) ODBC Driver Application Object System DSN Session object Database 14

Variables Every application uses variables, and ASP scripts are no exception! But there is no obligation in Visual Basic and Vb. Script No need to define the variables and variable types at the beginning of the program. But if you want you can. . . If you add the following line after the language info to the page; <% Option Explicit %> You must declare your variables. i. e. dim number 1 dim number 2 15

Variables Basic Variable Types: numeric, alpha-numeric, and logical. No need to know other variable types, because when you assign a value to a variable, Visual Basic understands your variable type! variable_1 = 15 variable_2 = “ 15” variable_3 = true If you want to learn type of any variable; <% variable_1 = 15 Response. write vartype(variable_1) ‘it writes 2 to the page %> List of Variant type variables of the VBScript vb. Null 1 contains no data, vb. Integer 2 integer type, vb. Long 3. . . 16

VBScript Looping – flow controls Looping constructs provide the foundation for any application that must repetitively perform a task. Such as adding 1 to a variable, reading a text file, or processing an e-mail message. VBScript and Jscript provide several looping mechanism. For. . . Next, For each. . . in. . . Next, Do. . Loop While, Do. . . While. . . Loop, Do. . Until. . . Loop, Do. . . Loop Until. . . , While. . . Wend conditional operators Conditional operators, together with variables and looping constructs, for the fundamental building blocks of applications. Such as sending a page to the client browser that consists of the current time and date and a greeting If. . Then, If. . . then. . . else, If. . . then. . . Elseif. . . then else, Select. . . Case, Switch. . case 17

How to Create ASP Pages? 1. Create your web page - basic design - with MS Frontpage 2. Switch to HTML tab. 3. Add ASP codes into their respective places. 4. Save your file with the extension. asp. 1. Design the followings in Front. Page: 18

How to Create ASP Pages ? 2. Switch to HTML tab. 19

How to Create ASP Pages? 3. Add ASP codes into their respective places. 20

Reponse. Write ( ) Response object is the part of ASP that handles responding to the request of a browser If you want to display information to Web page Write method of the response object will be used. <% Response. Write(“Hello World”) %> NOTE : equal sign (=) is a short-cut of response. write object <% = “Hello World” %> 21

How to Save ASP Pages? 4. Save your file with the extension. asp. OR Write asp extension with the file name. Select Active Server Pages option as file type. So, you do not need to write file extension. 22

How to transfer to the Server? 23

How to Display ASP Pages? 24

Another example! (“for – next”) We want to write “hosgeldiniz” in 5 different font size! 25

Handling HTML codes in ASP codes <% response. write “ “ & i%> <% Response. write “ ” %> html Tuna Tuna Tuna Tuna response. write “Tuna“ type. Mismatch 26

response. write “Tuna“ Handling Error: 1 st way: Do not use “ “ in HTML! But; face = lucida ? <% response. write<table width = 100%> %> ? 2 nd way: use ‘ ‘ instead of “ “ Examples: Example 1: Adding 2 numbers <% num 1 = 40 num 2 = 30 response. write num 1 + num 2 %> 27

response. write Example 2: finding y <% a=1 b=5 c=2 y= b*b - 4*a*c response. write y %> Example 3: finding the square of 2 numbers and the addition of their square <% num 1 = 10 num 2 = 20 sq 1 = num 1 * num 1 sq 2 = num 2 * num 2 sum = num 1 + num 2 response. write sq 2 &", "& sq 1 & ", " & sum 28

response. write & if. . then. . else. . end if Example 4: VAT included Price <% VAT = 18 PRICE = 3000000 VAT_INC = PRICE + (PRICE * VAT)/100 Response. Write "VAT included price is"& " " & VAT_INC %> Example 5: positive or negative? <% num = 89 IF num >0 THEN response. write num &" "& "is a positive number. “ ELSE response. write num &" "& "is a negative number. “ END IF %> 29

response. write & if. . then. . else. . end if Example 6: If a number less than 10, output it's square otherwise the number only. <% num = 9 IF num > 10 THEN sq = num * num response. write sq ELSE response. write num END IF %> Example 7: Subtract the smaller from the larger <% num 1 = 3 num 2 = 5 IF num 1>num 2 THEN num = num 1 - num 2 ELSE num = num 2 - num 1 END IF Response. Write num %> 30

response. write & if. . then. . else. . end if Example 8: SNG room 100$ others 150$> <% room_type = "DBL“ num_of_night = 10 IF room_type = "SNG" THEN price = 100 * num_of_night ELSE price = 150 * num_of_night END IF Response. Write "room price is " & price %> Example 9: PASS, FAIL <% final = 50 IF final >= 50 THEN Response. Write "PASS“ ELSE Response. Write "FAIL“ END IF %> 31