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1 CONTENT S.No Topics Page no 1 ASP 2 2 The benefits of ASP 4 3 Basic syntax rule of ASP 5 4 Working with scripting language 5 AD-Rotator 12 6 Explain some HTML forms 15 7 Cookies 22 8 Using Cookies in ASP 25 9 Connection Object Application Object P a g e

2 UNIT 1 ASP Active server pages (ASP) is a server-side scripting environment that can be used to create and run dynamic, interactive, high performance web application. ASP Model: Browser HTTP request Web server HTTP response An Asp script begins to run when a browser request an.asp file from the web server. An.asp file: ASP is built around files with the file name extension.asp. The ASP file contains *Text *HTML Tags *Script commands. The applications of ASP: 1. Completely integrated into HTML files. 2. Easy to create, with no manual compiling or links of programs required. 3. Object oriented and extensible with Active X Sever components. Script: A Script is a series of Sentences one below the other in the form of a paragraph. 2 P a g e

3 Five built- in objects in ASP: 1. Application 2. Request 3. Response 4. Server 5. Session Application object: Store and retrieve information that can be shared among all users of an application. Methods: Lock,Unlock Events: ApplicationOnEnd, ApplicationOnStart. Scripting Languages: A Script is a series of Sentences one below the other in the form of a paragraph. Intermediate Stage between HTML and programming languages. Formatting and linking text. Less rigid and less complex. VBScript (primary languages of ASP) COM:component object Model Example: JScript,perl,Javascript. Multiple script languages can be used with a single.asp file. What is the ASP? ASP (Active Server Pages) is a technology developed by Microsoft. Pages using ASP are primarily developed in JavaScript, VBScript, or PerlScript and are integrated into the HTML of your Web pages. The ASP code is compiled by the 3 P a g e

4 server and the resulting output is standard HTML. By using ASP, Web pages can be dynamic, full of ever-changing content, and browser independent The benefits of ASP ASP runs as a service of the Web server, and is optimized for multiple threads and multiple users. You can create ASP pages using whatever language you want. ASPs can also take advantage of COM and DCOM objects with minimum effort. Server-side scripts cannot be readily copied because only the result of the script is returned to the browser; users cannot view the script commands that created the page they are viewing. 4 P a g e

5 The Basic syntax rule of ASP ASP contains the server scripts, which can contain any expressions, statements, procedures, operators valid for the scripting language. These server scripts are enclosed by the delimiters and 1. VBScript 2. JavaScript 3. Other Scripting Languages 1. Request Object 2. Response Object 3. Server Object 4. Session Object 5. Application Objects ASP S object model 1. Request Object When a browser asks for a page from a server, it is called a request. The Request object is used to get information from a visitor. Its collections, properties, and methods are described below: Collections Collection Client Certificate Cookies Description Contains all the field values stored in the client certificate Contains all the cookie values sent in a HTTP request 5 P a g e

6 Form Query String Server Variables Contains all the form (input) values from a form that uses the post method Contains all the variable values in a HTTP query string Contains all the server variable values Properties Property TotalBytes Description Returns the total number of bytes the client sent in the body of the request Methods Method Binary Read Description Retrieves the data sent to the server from the client as part of a post request and stores it in a safe array Response Object The ASP Response object is used to send output to the user from the server. Its collections, properties, and methods are described below: Collections Collection Cookies Description Sets a cookie value. If the cookie does not exist, it will be created, and take the value that is specified 6 P a g e

7 Properties Property Buffer CacheControl Charset ContentType Expires ExpiresAbsolute IsClientConnected Pics Status Description Specifies whether to buffer the page output or not Sets whether a proxy server can cache the output generated by ASP or not Appends the name of a character-set to the content-type header in the Response object Sets the HTTP content type for the Response object Sets how long (in minutes) a page will be cached on a browser before it expires Sets a date and time when a page cached on a browser will expire Indicates if the client has disconnected from the server Appends a value to the PICS label response header Specifies the value of the status line returned by the server Methods Method AddHeader AppendToLog BinaryWrite Clear Description Adds a new HTTP header and a value to the HTTP response Adds a string to the end of the server log entry Writes data directly to the output without any character conversion Clears any buffered HTML output 7 P a g e

8 End Flush Redirect Write Stops processing a script, and returns the current result Sends buffered HTML output immediately Redirects the user to a different URL Writes a specified string to the output SESSION OBJECT: Collections Collection Contents Static Objects Description Contains all the items appended to the session through a script command Contains all the objects appended to the session with the HTML <object> tag Properties Property CodePage LCID SessionID Timeout Description Specifies the character set that will be used when displaying dynamic content Sets or returns an integer that specifies a location or region. Contents like date, time, and currency will be displayed according to that location or region Returns a unique id for each user. The unique id is generated by the server Sets or returns the timeout period (in minutes) for the Session object in this application 8 P a g e

9 Methods Method Abandon Contents. Remove Contents.RemoveAll() Description Destroys a user session Deletes an item from the Contents collection Deletes all items from the Contents collection Events Event Session_OnEnd Session_OnStart Description Occurs when a session ends Occurs when a session starts Server Object The ASP Server object is used to access properties and methods on the server. Its properties and methods are described below: Properties Property Script Timeout Description Sets or returns the maximum number of seconds a script can run before it is terminated Methods Method CreateObject Execute Description Creates an instance of an object Executes an ASP file from inside another ASP file 9 P a g e

10 GetLastError() HTMLEncode MapPath Transfer URLEncode Returns an ASPError object that describes the error condition that occurred Applies HTML encoding to a specified string Maps a specified path to a physical path Sends (transfers) all the information created in one ASP file to a second ASP file Applies URL encoding rules to a specified string Working with Scripting Languages Active Server Pages makes it possible for Web developers to write scripts that execute on the server in variety of scripting languages. In fact, several scripting languages can be used within a single.asp file. In addition, because scripts are read and processed on the server-side, the browser that requests the.asp file does not need to support scripting. You can use any scripting language for which the appropriate scripting engine is installed on your Web server. A scripting engine is a program that processes commands written in a particular language. Active Server Pages comes with two scripting engines: Microsoft Visual Basic Scripting Edition (VBScript) and Microsoft JScript. You can install and use engines for other scripting languages, such as REXX, PERL, and Python. Active Server Pages is a COM scripting host; to use a language you must install a scripting engine that follows the COM Scripting standard and resides as a COM (Component Object Model) object on the Web server. Setting the Primary Scripting Language 10 P a g e

11 The ASP primary scripting language is the language used to process commands inside the and delimiters. By default, the primary scripting language is VBScript. You can use any scripting language for which you have a script engine as the primary scripting language. You can set the primary scripting language on a page-by-page basis, or for all pages in an ASP application. Setting the Language for an Application To set the primary scripting language for all pages in an application, set the Default ASP Language property on the App Options tab in the Internet Information Services snap-in. Setting the Language for a Page To set the primary scripting language for a single page, add directive to the beginning of your.asp file. The syntax for using this directive LANGUAGE = "Scripting Language" where Scripting Language is the primary scripting language (such as VBScript, JScript, or PerlScript) that you want to set for that particular page. The setting for a page overrides the global setting for all pages in the application. 11 P a g e

12 UNIT-II EXPLAIN ABOUT AD-ROTATOR COMPONANT The Ad-rotator component is used to display a banner,advertisement on the web page of the web-site.this component can be used to specify how frequently different banner advertisement should be displayed. WHAT ARE ALL THE KEYWORD UAED IN FIRST SECTION OF THE ROTATOR SCHEDULE FILE? The keyword can be used in first section of rotator schedule file are: *REDIRECT-URL of file that implement redirection. WIDTH-Width of advertisement in pixels HEIGHT Height of advertisements in pixels. BORDER-Size of border WHAT DOES THE SECOND SECTION OF ROTATOR SCHEDULE FILE CONTAINS: The second section of rotator schedule file contains information about each image to be rotated.each image requires four lines of informations are: *the first line contain URLof advertisement image. *the second line contain URL of web page to which the graphic is linked. *the third line contain a text description of graphic. *the last line contains a number of times images to be displayed. EXPLAIN ABOUT BROWSER CAPABILITES COMPONENT; The browser capabilities component is very useful for developing crossbrowser web applications.when developing web applications,one cannot assume 12 P a g e

13 user employ the latest version of internet explorer. use the browser capabilities to determine which browser is employed by visitors and what browser support. DISCUSS SOME INFORMATON CAN OBTAINED USING BROWSER CAPABILITIES COMPONENT: *browser-name of web browser Version-version of the web browser. *majover-major version number. *platform-operating system being used. EXPLAIN ABOUT INPUTBOX FUNCTION; The inputbox function is displayed by a client-side VBscript subroutine.the inputbox function obtains input from a user by presenting a dialog box with data entry field.the syntax of inputbox command is Inputbox (<prompt>,<title>,<x>,<y>) *<prompt>-is the dialog box prompt. *<title>-is the title of dialog box. *<default>-is the default input value. <x>-is the horizontal position. *<y>-is the vertical position. EXPLAIN ABOUT MSGBOX FUNCTION: command is The msgbox function displays a message box.the syntax of msgbox Msgbox<msgbox prompt>-is the prompt of message box. 13 P a g e

14 *<buttonstyle>-is a number value *<title>-is the title of message box. DEFINE SOME MESSAGE BOX CODES FOR BUTTONS AND ICON; BUTTON ID NUMBER. 0 Ok 1 Ok and cancel 2 Abort,retry and ignore BUTTON ID NUMBER BUTTONS DISPLAYED 3 Yes no and cancel 14 P a g e

15 EXPLAIN SOME HTML FORMS; All web browser support html forms, so an asp application can use an html forms to communicate with virtually anyone browsing a website.asp application can easily access the values of an html form variable using request.query string method. Ex;Request.querysyring( name )-returns the value of name variable. EXPLAIN ABOUT RADIO BUTTONS WITH EXAMPLE: Radio button are useful when a user must be forced to make a choice from among a small number of choice in an html for Ex;<b>please enter you color :</b> <input name = color type= radio >red. <input name= color =type= radio >blue. <input type= submit value= submit > FIVEMARKS EXPLAIN THE ADVERTISEMENT ROTATOR COMPONENT; The advertisement rotator component is ideal for displaying a series of graphic images a text file containing information about images to be rotated and consist of two section separated by asterisk *the first section contains information about each image to be rotated 15 P a g e

16 Ex; 1.BORDER 4 2.* 3./IMAGES/WIMLOGO.gif EXPLAIN MSGBOX FUNCTION: The message box function display message box the syntax of masgbox command is: Msg box <msgbox prompt,<buttonstyle>,<title> Massage box s icon id number and some icon type. Are: 16-Critical Massage Box icon 32-warning query icon. Massage box s codes for some Button disply Are: 0-ok 1-ok 4-yes and no 6-retry and cancal ASP AdRotator Component The ASP AdRotator component creates an AdRotator object that displays a different image each time a user enters or refreshes a page. A text file includes information about the images. Note: The AdRotator does not work with Internet Information Server 7 (IIS7). Syntax 16 P a g e

17 set adrotator=server.createobject("mswc.adrotator") adrotator.getadvertisement("textfile.txt") ASP AdRotator Example Assume that we have the following text file, named "ads.txt": REDIRECT banners.asp * w3s.gif Free Tutorials from W3Schools 50 xmlspy.gif XML Editor from Altova 50 The lines below the asterisk in the text file above specifies the name of the images (ads) to be displayed, the hyperlink addresses, the alternate text (for the images), and the display rates (in percent). The first line in the text file above specifies what to happen when a visitor clicks on one of the images. The redirection page (banners.asp) will receive a querystring with the URL to redirect to. Tip: To specify the height, width, and border of the image, you can insert the following lines under REDIRECT: REDIRECT banners.asp WIDTH 468 HEIGHT 60 BORDER 0 * w3s.gif The "banners.asp" file looks like this: 17 P a g e

18 Example url=request.querystring("url") If url<>"" then Response.Redirect(url) <!DOCTYPE html> <html> <body> set adrotator=server.createobject("mswc.adrotator") response.write(adrotator.getadvertisement("textfile.txt")) </body> </html> ASP AdRotator Properties Property Description Example Border Specifies the size of the borders around the advertisement set adrot=server.createobject("mswc.adrotator") adrot.border="2" Response.Write(adrot.GetAdvertisement("ads.txt")) Clickable Specifies set whether the adrot=server.createobject("mswc.adrotator") advertisement is adrot.clickable=false a hyperlink Response.Write(adrot.GetAdvertisement("ads.txt")) TargetFrame Name of the 18 P a g e

19 frame to display the advertisement set adrot=server.createobject("mswc.adrotator") adrot.targetframe="target='_blank'" Response.Write(adrot.GetAdvertisement("ads.txt")) ASP Forms and User Input The Request.QueryString and Request.Form commands are used to retrieve user input from forms. Examples A form with method="get" How to interact with the user, with the Request.QueryString command. A form with method="post" How to interact with the user, with the Request.Form command. A form with radio buttons How to interact with the user, through radio buttons, with the Request.Form command. User Input The Request object can be used to retrieve user information from forms. User input can be retrieved with the Request.QueryString or Request.Form command. Request.QueryString The Request.QueryString command is used to collect values in a form with method="get". 19 P a g e

20 Information sent from a form with the GET method is visible to everyone (it will be displayed in the browser's address bar) and has limits on the amount of information to send. Example HTML form <form method="get" action="simpleform.asp"> First Name: <input type="text" name="fname"><br> Last Name: <input type="text" name="lname"><br><br> <input type="submit" value="submit"> </form> If a user typed "Bill" and "Gates" in the HTML form above, the URL sent to the server would look like this: Assume that "simpleform.asp" contains the following ASP script: <body> Welcome response.write(request.querystring("fname")) response.write(" " & request.querystring("lname")) </body> The browser will display the following in the body of the document: Welcome Bill Gates Request.Form The Request.Form command is used to collect values in a form with method="post". Information sent from a form with the POST method is invisible to others and has no limits on the amount of information to send. Example HTML form 20 P a g e

21 <form method="post" action="simpleform.asp"> First Name: <input type="text" name="fname"><br> Last Name: <input type="text" name="lname"><br><br> <input type="submit" value="submit"> </form> If a user typed "Bill" and "Gates" in the HTML form above, the URL sent to the server would look like this: Assume that "simpleform.asp" contains the following ASP script: <body> Welcome response.write(request.form("fname")) response.write(" " & request.form("lname")) </body> The browser will display the following in the body of the document: Welcome Bill Gates Form Validation User input should be validated on the browser whenever possible (by client scripts). Browser validation is faster and reduces the server load. You should consider server validation if the user input will be inserted into a database. A good way to validate a form on the server is to post the form to itself, instead of jumping to a different page. The user will then get the error messages on the same page as the form. This makes it easier to discover the error 21 P a g e

22 UNIT-III Purpose of Cookies: To identify viewers. To identify a PC that is sending a request. Application of Cookies: Cart expiration Personal Information User s name, geographic location, time zone and account number. Personal Preference-Preferred background color/bitmap, background music. Information about an Online Transaction-Items in shopping cart, time spent shopping, shopping time/date. Drawbacks of Using Cookies: Cookies can be lost. Cookies can be changed by users. Cookies can be copied. Cookies can be stolen. Creating Cookies: The Response Object is used to create a cookie and set its attributes. Cookies are created using the following syntax, Response.Cookies(NameOfCookie)=ValueOfCookie Eg: Response.Cookies( TimeZone )= Eastern. Setting Attributes of Cookies: Cookies can contain various attributes. Such as when the cookie expires and to which domain the cookie is sent Syntax: Response.Cookies(NameOfCookie).Cookie Attribute=Value of Cookie Attribute. ActiveX Data Objects: 22 P a g e

23 The ActiveX Data Objects provide an application level interface to data providers such as Microsoft SQL Server or Microsoft Access. ADO is directly used within Active Server Pages to communicate with such databases. Open Database Connectivity Interface: Open Database Connectivity Interface was used as the standard for communicating with databases. Microsoft has OLEDB providers for such databases as Microsoft SQL Server, Oracle and Microsoft Jet. Connection Object: The Connection Object represents all the features of a connection to the data source. Data Sources such as normal Text File, Microsoft Excel, Microsoft Exchange. Record set Object: A Record set object represents the rows of data returned from the data sources. Eg: A select query is fired on a database, the rows of data returned. Command Object: The Command Object represents a command that can be executed against a data source. Typically, the command object is used to execute a SQL stored procedure. DRAWBACKS OF COOKIES: Cookies can be lost: Cookies File can be corrupted, deleted or over written. Cookies can be changed by users: Cookies can be used to store non-confidential Information. 23 P a g e

24 Cookies can be copied: Cookies to store information that is unique to the user s computer. Cookies can be stolen: Cookies information can be copied. ADDRESSING THE DRAWBACKS OF COOKIES: Large Cookie Approach: It stores all of the information in the cookies itself. Minimalist Approach: It stores only an identify in the cookie. Middle Approach: Most commonly and urgently needed information held in the cookie. CONNECTING TO SQL SERVER WITH OLEDB: A connection to SQL server is opened with a connection string that contains Five Parameters: The OLEDB provider. The Datasource. The Database. The user Id. The Password. 24 P a g e

25 USING COOKIES IN ASP APPLICATIONS Creating Cookies: The Response Object is used to create a cookie. Syntax: Response.Cookies(NameOfCookie)=ValueOfCookie. Setting Attributes of Cookies: Cookies can contain various attributes such as when the cookie expires and to which domain the cookie is sent. Syntax: Response.Cookies(NameOfCookie).Cookie Attribute=ValueOfCookie Attribute. Storing Multiple Values in a cookie: Multiple values can be stored in a cookie by using keys. Syntax: Response.Cookies( NameOfCookie )( NameOfKey )=( ValueOfKey ) Retrieving a Single Value from a Cookie: Syntax: myvar=request.cookies(nameofcookie) Retrieving Multiple Values from Cookie Keys: Syntax:myvar=Request.Cookies( NameOfCookie )( Name of sub key ) Testing if a cookie has key values or not: Syntax: myvar=request.cookies( NameOfCookie ).Haskeys 25 P a g e

26 CONNECTING TO A MICROSOFT ACCESS DATABASE Creating a Microsoft Access Connection Using OLEDB: The preferred method for creating a connection to an access database is by using a native OLE DB provider. Creatin a MicroSoft Access Connection Using the ODBC: There are three choices. They are, store the information in Windows Registry, file, connection string itself. Creating a System DSN for MicroSoft Access: To store the connection information in the window registry, a system DSN must to be created. What is the ASP? ASP (Active Server Pages) is a technology developed by Microsoft. Pages using ASP are primarily developed in JavaScript, VBScript, or PerlScript and are integrated into the HTML of your Web pages. The ASP code is compiled by the server and the resulting output is standard HTML. By using ASP, Web pages can be dynamic, full of ever-changing content, and browser independent What is a Cookie? A cookie is often used to identify a user. A cookie is a small file that the server embeds on the user's computer. Each time the same computer requests a page with a browser, it will send the cookie too. With ASP, you can both create and retrieve cookie values. 26 P a g e

27 How to Create a Cookie? The "Response.Cookies" command is used to create cookies. Note: The Response.Cookies command must appear BEFORE the <html> tag. In the example below, we will create a cookie named "firstname" and assign the value "Alex" to it: Response.Cookies("firstname")="Alex" It is also possible to assign properties to a cookie, like setting a date when the cookie should expire: Response.Cookies("firstname")="Alex" Response.Cookies("firstname").Expires=#May 10,2012# How to Retrieve a Cookie Value? The "Request.Cookies" command is used to retrieve a cookie value. In the example below, we retrieve the value of the cookie named "firstname" and display it on a page: fname=request.cookies("firstname") 27 P a g e

28 response.write("firstname=" & fname) Output: Firstname=Alex A Cookie with Keys If a cookie contains a collection of multiple values, we say that the cookie has Keys. In the example below, we will create a cookie collection named "user". The "user" cookie has Keys that contains information about a user: Response.Cookies("user")("firstname")="John" Response.Cookies("user")("lastname")="Smith" Response.Cookies("user")("country")="Norway" Response.Cookies("user")("age")="25" Read all Cookies Look at the following code: Response.Cookies("firstname")="Alex" Response.Cookies("user")("firstname")="John" Response.Cookies("user")("lastname")="Smith" Response.Cookies("user")("country")="Norway" 28 P a g e

29 Response.Cookies("user")("age")="25" Assume that your server has sent all the cookies above to a user. Now we want to read all the cookies sent to a user. The example below shows how to do it (note that the code below checks if a cookie has Keys with the HasKeys property): <!DOCTYPE html> <html> <body> dim x,y for each x in Request.Cookies response.write("<p>") if Request.Cookies(x).HasKeys then for each y in Request.Cookies(x) response.write(x & ":" & y & "=" & Request.Cookies(x)(y)) response.write("<br>") next else Response.Write(x & "=" & Request.Cookies(x) & "<br>") end if response.write "</p>" next 29 P a g e

30 </body> </html> Output: firstname=alex user:firstname=john user:lastname=smith user:country=norway user:age=25 COOKIES EXAMPLE: dim numvisits response.cookies("numvisits").expires=date+365 numvisits=request.cookies("numvisits") if numvisits="" then response.cookies("numvisits")=1 response.write("welcome! This is the first time you are visiting this Web page.") else response.cookies("numvisits")=numvisits+1 response.write("you have visited this ") response.write("web page " & numvisits) if numvisits=1 then 30 P a g e

31 response.write " time before!" else response.write " times before!" end if end if <!DOCTYPE html> <html> <body> </body> </html> OUTPUT Welcome! This is the first time you are visiting this Web page. 2. Use a form You can use a form. The form passes the user input to "welcome.asp" when the user clicks on the Submit button: <form method="post" action="welcome.asp"> First Name: <input type="text" name="fname" value=""> Last Name: <input type="text" name="lname" value=""> <input type="submit" value="submit"> </form> 31 P a g e

32 Retrieve the values in the "welcome.asp" file like this: fname=request.form("fname") lname=request.form("lname") response.write("<p>hello " & fname & " " & lname & "!</p>") response.write("<p>welcome to my Web site!</p>") What is ADO? ADO is a Microsoft technology ADO stands for ActiveX Data Objects ADO is a Microsoft Active-X component ADO is automatically installed with Microsoft IIS ADO is a programming interface to access data in a database Accessing a Database from an ASP Page The common way to access a database from inside an ASP page is to: 1. Create an ADO connection to a database 2. Open the database connection 3. Create an ADO recordset 4. Open the recordset 5. Extract the data you need from the recordset 6. Close the recordset 7. Close the connection 32 P a g e

33 Create an ODBC Database Connection If you have an ODBC database called "northwind" you can connect to the database with the following ASP code: set conn=server.createobject("adodb.connection") conn.open "northwind" With an ODBC connection, you can connect to any database, on any computer in your network, as long as an ODBC connection is available. An ODBC Connection to an MS Access Database Here is how to create a connection to a MS Access Database: 1. Open the ODBC icon in your Control Panel. 2. Choose the System DSN tab. 3. Click on Add in the System DSN tab. 4. Select the Microsoft Access Driver. Click Finish. 5. In the next screen, click Select to locate the database. 6. Give the database a Data Source Name (DSN). 7. Click OK. Note that this configuration has to be done on the computer where your web site is located. If you are running Personal Web Server (PWS) or Internet Information Server (IIS) on your own computer, the instructions above will work, but if your web site is located on a remote server, you have to have physical access to that server, or ask your web host to do this for you. 33 P a g e

34 The ADO Connection Object The ADO Connection object is used to create an open connection to a data source. Through this connection, you can access and manipulate a database. Create an ADO Table Recordset After an ADO Database Connection has been created, as demonstrated in the previous chapter, it is possible to create an ADO Recordset. Suppose we have a database named "Northwind", we can get access to the "Customers" table inside the database with the following lines: set conn=server.createobject("adodb.connection") conn.provider="microsoft.jet.oledb.4.0" conn.open "c:/webdata/northwind.mdb" set rs=server.createobject("adodb.recordset") rs.open "Customers", conn Create an ADO SQL Recordset We can also get access to the data in the "Customers" table using SQL: set conn=server.createobject("adodb.connection") conn.provider="microsoft.jet.oledb.4.0" conn.open "c:/webdata/northwind.mdb" 34 P a g e

35 set rs=server.createobject("adodb.recordset") rs.open "Select * from Customers", conn Extract Data from the Recordset After a recordset is opened, we can extract data from recordset. Suppose we have a database named "Northwind", we can get access to the "Customers" table inside the database with the following lines: set conn=server.createobject("adodb.connection") conn.provider="microsoft.jet.oledb.4.0" conn.open "c:/webdata/northwind.mdb" set rs=server.createobject("adodb.recordset") rs.open "Select * from Customers", conn for each x in rs.fields response.write(x.name) response.write(" = ") response.write(x.value) next 35 P a g e

36 Connect to MS SQL Server database from ASP This article shows how to connect to MySQL database from Classic ASP. You can connect to your MS SQL Server database OLEDB provider or SQL Server driver. The first example show how to connect to MS SQL db from ASP with the OLDEB provider: 1. ASP to MS SQL Server database connection with OLE DB: Set oconnection = Server.CreateObject("ADODB.Connection") oconnection.open "Provider=SQLOLEDB; Data Source=; Initial Catalog=; User ID=; Password=" oconnection.close Set oconnection = Nothing The example above just opens a connection from ASP to a SQL Server database and then closes it immediately. Most likely you will want to do more than just connecting to the db, but this is out of the scope of this article. 2. ASP to MS SQL Server database connection with SQL Driver: Set oconnection = Server.CreateObject("ADODB.Connection") oconnection.open "Driver={SQL Server};" & _ "Server=;" & _ "Database=;" & _ 36 P a g e

37 "Uid=;" & _ "Pwd=;" oconnection.close Connect with a DSN: DSN stands for 'Data Source Name'. It is an easy way to assign useful and easily rememberable names to data sources which may not be limited to databases alone. If you do not know how to set up a system DSN read our tutorial 'declare the variables Dim Connection Dim Recordset Dim SQL 'declare the SQL statement that will query the database SQL = "SELECT * FROM TABLE_NAME" 'create an instance of the ADO connection and recordset objects Set Connection = Server.CreateObject("ADODB.Connection") Set Recordset = Server.CreateObject("ADODB.Recordset") 'open the connection to the database Connection.Open "DSN=dsn_name;UID=user_name;PWD=password;Database=database_name" 37 P a g e

38 'Open the recordset object executing the SQL statement and return records Recordset.Open SQL,Connection 'first of all determine whether there are any records If Recordset.EOF Then Response.Write("No records returned.") Else 'if there are records then loop through the fields Do While NOT Recordset.Eof Response.write Recordset("FIRST_FIELD_NAME") Response.write Recordset("SECOND_FIELD_NAME") Response.write Recordset("THIRD_FIELD_NAME") Response.write "<br>" Recordset.MoveNext Loop End If 'close the connection and recordset objects to free up resources Recordset.Close Set Recordset=nothing Connection.Close Set Connection=nothing 38 P a g e

39 UNIT-IV Connection Object: The Connection Object is directly related to command & recordset object other object can be created independently; they cannot communicate with a data source without going through the connection objet. Record set A record set can be used to represent the rows returned from a SQL query within an active server page script. Record set Object: A record set object can be used to represent only a single row or it can be used to represent dozens or even millions of rows. The same object is used no matter how much data is returned by a query. Record set Fields: Each record set contain field s collection it contains individual fields object. the fields in the fields collection represent the columns returned from the database query. Record set cursor: Whenever a record set is opened, either implicity or explicity a cursor is created in memory which will have a behavior called locking associated with it ADO cursor There are different types of ADO cursors *Forward only cursor *static cursor *keyset driven cursor *dynamic cursor 39 P a g e

40 Properties of field object *Actual size *Attributes *defined size *Name ADO locking types: The locktype property can have the value explain below *adlock readonly-the data cannot be altered *adlock pessimistic-other user are prevented from accessing the data *adlock optimistic-other user can access the record until the changes are actually committed *adlockbatch optimistic-this is used when performing batch updates Executing an SQL statement with the connection object: (i) creating a new database table (ii)inserting data into a database table (iii)updating data in a database table (iv)deleting data in a database table (V)selecting data from a database table 40 P a g e

41 Properties of field object: *Actualsize *Attributes *Defined size *Name *Numeric scale *Original value *precision *Type *Underlying value *Value ADO Cursor types forward only cursor *all the results are fetched *do not support backward scrolling static cursor *can scroll back and forth through the result set keyset-driven cursor *certain changes can be made *Supports scrolling dynamic cursor *fully supports scrolling 41 P a g e

42 How do you execute SQL statement with the connection object: *creating a new database table *inserting data into database table *updating data in a database table *selecting data from the database table advanced methods &properties of connection object Recordset cursor and locking types: *understanding ADO cursors *forward only cursor *static cursor *keyset-driven cursor *dynamic cursor *client-side&serverside cursor *understanding ADO locking types ASP Session Object A Session object stores information about, or change settings for a user session. The Session object ASP solves this problem by creating a unique cookie for each user. The cookie is sent to the user's computer and it contains information that identifies the user. This interface is called the Session object. The Session object stores information about, or change settings for a user session. When does a Session Start? A session starts when: 42 P a g e

43 A new user requests an ASP file, and the Global.asa file includes a Session_OnStart procedure A value is stored in a Session variable A user requests an ASP file, and the Global.asa file uses the <object> tag to instantiate an object with session scope When does a Session End? A session ends if a user has not requested or refreshed a page in the application for a specified period. By default, this is 20 minutes. If you want to set a timeout interval that is shorter or longer than the default, use the Timeout property. The example below sets a timeout interval of 5 minutes: Session.Timeout=5 Use the Abandon method to end a session immediately: Session.Abandon Note: The main problem with sessions is WHEN they should end. We do not know if the user's last request was the final one or not. So we do not know how long we should keep the session "alive". Waiting too long for an idle session uses up resources on the server, but if the session is deleted too soon the user has to start all over again because the server has deleted all the information. Finding the right timeout interval can be difficult! Tip: Only store SMALL amounts of data in session variables! Store and Retrieve Session Variables 43 P a g e

44 The most important thing about the Session object is that you can store variables in it. The example below will set the Session variable username to "Donald Duck" and the Session variable age to "50": Session("username")="Donald Duck" Session("age")=50 When the value is stored in a session variable it can be reached from ANY page in the ASP application: Welcome Response.Write(Session("username")) The line above returns: "Welcome Donald Duck". You can also store user preferences in the Session object, and then access that preference to choose what page to return to the user. The example below specifies a text-only version of the page if the user has a low screen resolution: If Session("screenres")="low" Then This is the text version of the page Else This is the multimedia version of the page End If Remove Session Variables The Contents collection contains all session variables. It is possible to remove a session variable with the Remove method. The example below removes the session variable "sale" if the value of the session variable "age" is lowers than 18: 44 P a g e

45 If Session.Contents("age")<18 then Session.Contents.Remove("sale") End If To remove all variables in a session, use the RemoveAll method: Session.Contents.RemoveAll() Loop through the Contents Collection The Contents collection contains all session variables. You can loop through the Contents collection, to see what's stored in it: Session("username")="Donald Duck" Session("age")=50 dim i For Each i in Session.Contents Response.Write(i & "<br>") Next Result: username age If you do not know the number of items in the Contents collection, you can use the Count property: dim i dim j 45 P a g e

46 j=session.contents.count Response.Write("Session variables: " & j) For i=1 to j Response.Write(Session.Contents(i) & "<br>") Next Result: Session variables: 2 Donald Duck 50 Loop Through the StaticObjects Collection You can loop through the StaticObjects collection, to see the values of all objects stored in the Session object: dim i For Each i in Session.StaticObjects Response.Write(i & "<br>") Next ADO (ActiveX Data Objects) This describes database connectivity with ADO (ActiveX Data Objects) and how you can use this to communicate and manage a database server. You will learn how to open a connection to a database, run INSERT, UPDATE, DELETE, and SELECT statements as well as execute a stored procedure. Content Active Server Pages, being a scripted language, is a stateless language. By this, we mean that it doesn't preserve the state of the application between page loads. 46 P a g e

47 Nearly all ASP hosting solutions will include some sort of database hosting. Most common is MySQL, followed by Microsoft SQL Server. No matter what database you are using, ADO will allow you to manage the database through Active Server Pages. While it's true that you can store persistant data in the Application object. This is basically just stored in a memory cache that will be flushed whenever IIS or the server is restarted. It also causes problems when trying to create an application which will be used in a server cluster (where each cluster has its own version of the Application cache.) Connecting to a Database Here is a sample showing how to open a connection to a database. To do this, we call the Server.CreateObject to create an instance of the built-in ADODB Connection object. Not only is this used to create the initial connection to the database, it will also be used to create the Recordset and Command Objects later. You will need to replace the text mysqluser, mysqlpass, and mysqldbname with the correct values for your database. Note that this is accessing a MySQL server on the local server (localhost) using ODBC. ' create a connection object Set oconnection = Server.CreateObject("ADODB.Connection") ' open a connection to a data source oconnection.open "Driver={MySQL ODBC 3.51 Driver};server=localhost;port=3306;uid=mysqluser;pwd=mysqlpass;database=mys qldbname;option=16384" 47 P a g e

48 Note that you could wrap this statement with an On Error block to trap any exceptions that may occur. INSERT, UPDATE, and DELETE The following will use the ADODB.Connection object to run an INSERT query on the database. The code is the same whether you are doing INSERT, UPDATE, or DELETE. You only need to change the squery variable with your modified query. ' build the query to run squery ="INSERT INTO Company VALUES ("Microsoft")" ' execute the insert statement oconnection.execute squery, nrecordsaffected, adcmdtext + adexecutenorecords Response.Write "Records Affected: " & nrecordsaffected The constants adcmdtext and adexecutenorecords are described in the section ADO Constants. SELECT The following code can be used to run a SELECT statement against a database. You must first open a connection to a database using the code described in the section Connecting to a Database. squery = "SELECT companyid, companyname FROM tblcompany" 48 P a g e

49 ' create the recordset object to hold the result sets Set rs = Server.CreateObject("ADODB.Recordset") ' set the number of records to fetch into memory at once (performance) rs.cachesize = 256 ' execute the query and populate the recordset rs.open squery, oconnection, adopenkeyset, adlockreadonly, adcmdtext 'More examples of SELECT (based on criteria) are: '*example 1. squery = "SELECT companyid, companyname FROM tblcompany WHERE companyid = 1" '1. See details below 1. When squery in above code snippet is set as example 1. it will fetch records with companyid having value 1, in this SQL statement WHERE clause is used to define that criteria. The constants adopenkeyset, adlockreadonly, and adcmdtext are described in the section ADO Constants. Now that you have opened a recordset, what can you do with it? Retrieving the Recordset The following code will show you how to use the recordset object (rs) described in the SELECT section to retrieve values from your database query. ' EOF checks for the end of a recordset If Not rs.eof Then 49 P a g e

50 ' The Fields collection accesses fields from a single record sfirstname = rs.fields("firstname").value ' You can enumerate all fields in the record For Each ofld In rs.fields Response.Write "Field = " & ofld.name & "<br>" Response.Write "Value = " & ofld.value & "<br>" Next End If ' You can also loop through all records Do Until rs.eof Response.Write "Name = " & rs.fields("firstname").value & "<br>" ' make sure you don't forget this next step ' MoveNext will move to the next record in the resultset rs.movenext Loop ' following is always a good idea to clean up resources ASAP rs.close : rs = 0 Closing a Database Connection You should always close your database connection when you are done accessing the database. It is not required, but it is always a good idea. ' it's a good idea to close your recordset first (if necessary) rs.close : rs = 0 ' this will close the database connection oconnection.close 50 P a g e

51 ADO Constants Variable 'adopenkeyset adlockreadonly adlockpessimistic adlockoptimistic adcmdtext adcmdtable Open a keyset Const adopenkeyset = 1 Purpose Create a database lock for read only access to a table. This is a forward-only cursor which provides the most efficient method for retrieving results. Const adlockreadonly = 1 This locking method will lock a database record as soon as edits have been made to the database. (Not really used in Active Server Pages) Const adlockpessimistic = 2 Use optimistic record locking on the database records. Meaning a record will only be locked when records have been modified and edits are committed back to the database. (Not really used in Active Server Pages) Const adlockoptimistic = 3 Indicates the SQL command being passed is text (an SQL statement) Const adcmdtext = 1 Indicates the SQL command being passed is the name of a database table to open (all rows and fields) adcmdstoredproc Const adcmdtable = 2 Indicates the SQL command being passed is the name of a stored procedure to execute. When using this call, the parameters must be defined separately. Const adcmdstoredproc = 4 51 P a g e

52 UNIT-V ASP Application Object A group of ASP files that work together to perform some purpose is called an application. The Application object is used to tie these files together. Application Object An application on the Web may consist of several ASP files that work together to perform some purpose. The Application object is used to tie these files together. The Application object is used to store and access variables from any page, just like the Session object. The difference is that ALL users share ONE Application object (with Sessions there is ONE Session object for EACH user). The Application object holds information that will be used by many pages in the application (like database connection information). The information can be accessed from any page. The information can also be changed in one place, and the changes will automatically be reflected on all pages. The Application object's collections, methods, and events are described below: Collections Collection Contents StaticObjects Description Contains all the items appended to the application through a script command Contains all the objects appended to the application with the HTML <object> tag 52 P a g e

53 Methods Method Contents.Remove Contents.RemoveAll() Lock Unlock Description Deletes an item from the Contents collection Deletes all items from the Contents collection Prevents other users from modifying the variables in the Application object Enables other users to modify the variables in the Application object (after it has been locked using the Lock method) Events Event Application_OnEnd Application_OnStart Description Occurs when all user sessions are over, and the application ends Occurs before the first new session is created (when the Application object is first referenced) Store and Retrieve Application Variables Application variables can be accessed and changed by any page in an application. You can create Application variables in "Global.asa" like this: <script language="vbscript" runat="server"> Sub Application_OnStart application("vartime")="" application("users")=1 53 P a g e

54 End Sub </script> In the example above we have created two Application variables: "vartime" and "users". You can access the value of an Application variable like this: There are Response.Write(Application("users")) active connections. Loop Through the Contents Collection The Contents collection contains all application variables. You can loop through the Contents collection, to see what's stored in it: dim i For Each i in Application.Contents Response.Write(i & "<br>") Next If you do not know the number of items in the Contents collection, you can use the Count property: dim i dim j j=application.contents.count For i=1 to j Response.Write(Application.Contents(i) & "<br>") Next 54 P a g e

55 Loop Through the StaticObjects Collection You can loop through the StaticObjects collection, to see the values of all objects stored in the Application object: dim i For Each i in Application.StaticObjects Response.Write(i & "<br>") Next Lock and Unlock You can lock an application with the "Lock" method. When an application is locked, the users cannot change the Application variables (other than the one currently accessing it). You can unlock an application with the "Unlock" method. This method removes the lock from the Application variable: Application.Lock 'do some application object operations Application.Unlock 55 P a g e

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