What are three categories of Perl variables? Give Examples for each.

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1 INTERNAL ASSESSMENT TEST II Solution manual With neat figure explain common gateway interface and mention different client side and server side components. (10 Marks) 2 a) b) What are three categories of Perl variables? Give Examples for each. Write a Perl program using exists function to find whether an item exists or not in an associative array. 3 Write a PERL Program to insert student details(usn, name and total marks) into MY SQL VTU database and display top 3 students (Based on percentage). (10 Marks) 4 a) b) What is CSS? Explain with examples various levels of CSS. Explain with examples various ways of accessing HTML controls in Java Script. 5 a) What is cookie? Write a PERL program to create visiting cookie. b) Write a java script program to validate phone number field(valid number format is country code-ten digit mobile number, Ex: is valid number)

2 1. With neat figure explain common gateway interface and mention different client side and server side components Common gateway interface HTML files on server Server Client Web Browser url Internet url Web Server url + data url + data script CGI environment (CGI scripts) Cache Case 1 : Client sends request for HTML document, and the Web Server returns HTML document. Ex: DB Server DB ODBC Case 2: Client sends CGI script request, Web Server passes request to the CGI, CGI processes the data with the script, and returns an HTML document plus data, if necessary). Ex: Ex: Client side components ` HTML,Java Script, CSS,XML.etc Server side components PERL,PHP,Servlets,EJB, etc..

3 Q 2 a) What are three categories of Perl variables? Give Examples for each. Scalars Arrays Hashes Scalar Variables A scalar is a single unit of data. That data might be an integer number, floating point, a character, a string, a paragraph, or an entire web page. Simply saying it could be anything, but only a single thing. Here is a simple example of using scalar variables #!/usr/bin/perl $age = 25; # An integer assignment $name = "kumar"; # A string $salary =50000; # A floating point print "Age = $age\n"; print "Name = $name\n"; print "Salary = $salary\n"; Array Variables An array is a variable that stores an ordered list of scalar values. Array variables are preceded by an "at" (@) sign. To refer to a single element of an array, you will use the dollar sign ($) with the variable name followed by the index of the element in square brackets. Here is a simple example of using array variables #!/usr/bin/perl

4 @ages = (25, 30, = ("John Paul", "Lisa", "Kumar"); print "\$ages[0] = $ages[0]\n"; print "\$ages[1] = $ages[1]\n"; print "\$ages[2] = $ages[2]\n"; print "\$names[0] = $names[0]\n"; print "\$names[1] = $names[1]\n"; print "\$names[2] = $names[2]\n"; Hash Variables A hash is a set of key/value pairs. Hash variables are preceded by a percent (%) sign. To refer to a single element of a hash, you will use the hash variable name followed by the "key" associated with the value in curly brackets. Here is a simple example of using hash variables #!/usr/bin/perl %data = ('John Paul', 45, 'Lisa', 30, 'Kumar', 40); print "\$data{'john Paul' = $data{'john Paul'\n"; print "\$data{'lisa' = $data{'lisa'\n"; print "\$data{'kumar' = $data{'kumar'\n"; Q 2b) Write a Perl program using exists function to find whether an item exists or not in an associative array Exists function(exists) Used to find whether an item exists or not %arr=(123,"ram",124,"rahul",125,"ravi"); $val=<stdin>; chomp($val); if(exists($arr{$val)) { print "YES"; else

5 { print "No"; Q 3) Write a PERL Program to insert student details(usn, name and total marks) into MY SQL VTU database and display top 3 students (Based on percentage). use CGI ':standard'; use DBI; print header(); $name=param( txtname ); $usn=param( txtusn ); $per=param( txtper ); $con=dbi->connect("dbi:mysql:vtu","root",""); $stat1=$con->prepare("insert into student values(?,?,?)"); $stat1->execute($name,$usn,$per); $stat2=$con->prepare("select *from student order by percentage desc limit 3"); $stat2->execute(); print "Top three students are <BR>"; while(@row=$stat2->fetchrow_array()) { print "@row <BR>"; print end_()

6 Q 4 a) What is CSS? Explain with examples various levels of CSS. CSSs provide the mechanism to control and change presentation of HTML documents CSS is not HTML, but can be embedded in HTML documents A style sheet is a mechanism for specifying style information CSS is designed to enable the separation of content from document presentation 1.inline CSS <p style=". ">Hello CSS</p> Example <p style="color:red;font-size:50;text-decoration:blink;text-align:center">hello CSS</p> 2.Document Level CSS <Style type= text/css > style specifications here </style> Doc level CSS can be created Using Style tag and it is placed within the head tag <> <body> <p style="background:blue; font-size:30px; color:red; border:solid black 10px; text-align: center; font-family:elephant; margin:100px; " > Hello world by inline level CSS </p>

7 </body> <> External Level CSS <link> tag is used to specify that the browser is to fetch and use an external style sheet file <link rel="stylesheet" type="text/css" href="style.css" /> Styles specifications are stored in style.css file Q 4 b) Explain with examples various ways of accessing HTML controls in Java Script. 1) Using Arrays (form and elements array) Ex var data=document.forms[0].elements[0].value; Problem is that, if we add some elements in between then, index number will change. Then some elements will not be accessible Ex: 2) Using Name of the control <input type= text name= txtusername > var data=document.loginform.txtusername.value; Ex: Problem is, it is not suggested to use name attribute in XHTML, name attribute is deprecated. 3) Using getelementbyid() method <input type= text id= txtusername > var data=document.getelementbyid( txtusername ).value;

8 Q 5 a) What is cookie? Write a PERL program to create visiting cookie. A cookie is a piece of information Cookie will have a name, value and age or expiry date The function cookie() is used to create and to read cookie cookie( cname ); returns the values stored in the cookie called cname as an array. PERL program to create visiting cookie use CGI qw(:standard); print if(scalar(@last_visit)==0) { print "you are visiting for the first time"; Else { print Welcome,your last visit was $k=localtime(time()); $day_cookie=cookie(-name=>'last_time',-value=>$k,-expires=>'+5d'); print header(-cookie=>$day_cookie); print end_(); Q 5 b) Write a java script program to validate phone number field(valid number format is country code-ten digit mobile number, Ex: is valid number) <script type="text/javascript"> function validate() { var k=document.getelementbyid("txtphone"); var pat=k.value.match(/^\d{2-\d{10$/); alert(pat); if(!pat) { alert("pls enter"); k.select(); return false; return true; </script></head> <body bgcolor='silver'> <form> USN:<input type="text" id="txtphone" name="txtusn">ex: <input type="button" value="check" onclick="validate();"> </form>