Part 4 - Server side Handling data with PHP

Question 1

An array that contains keys and values sent to the server on the end of the URL or by submitting a HTML form using the GET method.

Answer 1

describe the superglobal variable
$_GET

Question 2

Basic syntax (arguments omitted):
define(name,value)

@param name (Required) Specifies the name of the constant
@param value (Required) Specifies the value of the constant.

Answer 2

describe the syntax and parameters of

define()

Question 3

what are the syntax and parameters of

var_export()

Answer 3

Syntax:
var_export(variable,return);

@param variable (Required). Specifies the variable to check
@param return (Optional). If set to true, it returns the variable representation instead
of outputting it

Question 4

describe the function

var_export()

Answer 4

a function that outputs or returns structured information about a variable.

Question 5

describe the superglobal variable
$_GET

Answer 5

An array that contains keys and values sent to the server on the end of the URL or by submitting a HTML form using the GET method.

Question 6

describe the function

define()

Answer 6

this function is used to define a constant

Question 7

describe the syntax and parameters of

empty()

Answer 7

Syntax:
empty(variable);

@param variable (Required) Specifies the variable to check

Question 8

function used for case insensitive comparison of two strings, returns 0 if the two strings match

Answer 8

describe the function

strcasecmp()

Question 9

give 3 points that describe
Java

Answer 9

points on this include:
1.Open source
2.Object oriented
3.When used to serve dynamic web content a special web server is required such as Tomcat

Question 10

describe the function

htmlspecialchars()

Answer 10

a function that converts some predefined characters to HTML entities.

Question 11

describe the function

strcasecmp()

Answer 11

function used for case insensitive comparison of two strings, returns 0 if the two strings match

Question 12

describe the
difference between declaring strings with single vs double quotes

Answer 12

Single quotes - these are interpreted exactly as written and so the text within the single quotes will always be unchanged

Double quotes - anything written within double quotes will be interpreted by PHP, this means if a variable name is included it will be evaluated and replaced by its value. Any other escape sequences will also be interpreted within double quotes

Question 13

To implement this:
1.We set a flag in PHP files that will be requested by URL, the flag states that it is safe for files to run
a)This can be achieved setting a constant using define() function
2.Files that should only be executed via require or include will look for the flag, if it is not set then they will refuse to execute
a)This can be achieved by:
b)Checking if flag is set using the defined() function
c)If the flag is not set we terminate the script using the die() method

This ensures that users can only execute the scripts that we intend them to execute,

Answer 13

describe the implementation that would mitigate users executing the scripts that we will call using the require and include statements

Question 14

this can be mitigated by cleaning text of any characters that could hold code before it is sent to the users browser.

we can accomplish this by using the function htmlspecialchars(). which replaces HTML characters with HTML entities

Answer 14

give one example of how a
Cross site scripting (XSS) attack can be mitigated
in PHP

Question 15

when we access an array we should always check to see if it is empty.

the reason being because if we access an element that is not there then PHP will output a notice in the HTML. this should be hidden

Answer 15

when accessing an array what action should we perform first and why

Question 16

these include:
1.Hypertext Preprocessor (PHP)
2.Active Server Pages.NET (ASP.NET)
3.Java
4.Python
5.Node.js

Answer 16

name 5
server side programming languages

Question 17

Example:
$array = [];
if (!empty($array[‘id’])) {
Code if value exists;
} else {
Code if value does not exist;
}

Answer 17

give an example that checks if an array has content using an if…else statement

Question 18

give an example that checks if an array has content using an if…else statement

Answer 18

Example:
$array = [];
if (!empty($array[‘id’])) {
Code if value exists;
} else {
Code if value does not exist;
}

Question 19

using a for each loop write the syntax for extracting the key and value of the current element

Answer 19

syntax:

foreach ($array as $key => $value) {
Code to execute;
}

Question 20

points on this include:
1.Open source
2.Object oriented
3.When used to serve dynamic web content a special web server is required such as Tomcat

Answer 20

give 3 points that describe
Java

Question 21

sometimes known as a dictionary is an array with named keys and associated values for each key

Answer 21

describe an
Associative arrays

Question 22

An array that contains data previously stored on the server in the current session

Answer 22

describe the superglobal variable
$_SESSION

Question 23

how do we
declare a constant in PHP

Answer 23

this is accomplished by using the define() function

Question 24

An array that contains keys and values sent to the server by submitting a HTML form using the POST method.

Answer 24

describe the superglobal variable
$_POST

Question 25

this is an array that contains data about the server running the PHP script.

Answer 25

describe the superglobal variable
$_SERVER

Question 26

we acieve this by using:

<?php
code
?>

Answer 26

how is PHP code placed inside a PHP document

Question 27

describe the syntax and parameters of

htmlspecialchars()

Answer 27

Basic syntax (arguments ommitted)
htmlspecialchars(string)

@param string the string to convert

Question 28

describe the implementation that would mitigate users executing the scripts that we will call using the require and include statements

Answer 28

To implement this:
1.We set a flag in PHP files that will be requested by URL, the flag states that it is safe for files to run
a)This can be achieved setting a constant using define() function
2.Files that should only be executed via require or include will look for the flag, if it is not set then they will refuse to execute
a)This can be achieved by:
b)Checking if flag is set using the defined() function
c)If the flag is not set we terminate the script using the die() method

This ensures that users can only execute the scripts that we intend them to execute,

Question 29

describe the function

basename()

Answer 29

this function returns the filename from a path.

Question 30

describe the 5
values that are considered
falsey

Answer 30

these include:
1.integer 0 and float 0.0
2.the empty string “” and “0” (because it is equivalent to integer 0)
3.an empty array []
4.the null value
5.and of course, the boolean false

Question 31

Syntax:
strcasecmp(string1,string2)

@param string1 (Required) Specifies the first string to compare
@param string2 (Required) Specifies the second string to compare

Answer 31

describe the syntax and parameters of

strcasecmp()

Question 32

this function checks whether a variable/array is empty or not. This function returns false if the variable exists and is not empty, otherwise it returns true.

Answer 32

describe the function

empty()

Question 33

how can we
remove an item from an array

Answer 33

this can be accomplished by using the unset() function

Question 34

points on this include:
1.Used by youtube and dropbox
2.Usefull for processing large data sets and scientific and statistical data
3.SQLLite is a database that is included with python

Answer 34

give 3 points that describe
python

Question 35

give one example of how a
Cross site scripting (XSS) attack can be mitigated
in PHP

Answer 35

this can be mitigated by cleaning text of any characters that could hold code before it is sent to the users browser.

we can accomplish this by using the function htmlspecialchars(). which replaces HTML characters with HTML entities

Question 36

describe the superglobal variable
$_POST

Answer 36

An array that contains keys and values sent to the server by submitting a HTML form using the POST method.

Question 37

what is the syntax of the PHP while loop

Answer 37

Syntax:

while (condition is true) {
code to be executed;
}

Question 38

describe the syntax and parameters of

unset()

Answer 38

Syntax:
unset(variable, ….);

@param variable (Required). Specifies the variable or array value to unset
@param … (Optional) Another variable to unset

Question 39

this function prints a message and terminates the current script.

Answer 39

describe the function

Die()

Question 40

describe the 2 types of arrays that can be created

Answer 40

these include:
1.Lists - where an index number is automatically associated with a value
2.Dictianories (Associative array) - where we specify a key and a value for the element in the array

NOTE:
* each key of a dictionary must be unique
* The key of a dictionary can be an integer or string

Question 41

write out the syntax for an
if…elseif…else block

Answer 41

Syntax:

if (condition) {
code to be executed if this condition is true;
} elseif (condition) {
code to be executed if first condition is false and this condition is true;
} else {
code to be executed if all conditions are false;
}

Question 42

points on this include:
1.Provides a javascript runtime on the server
2.Efficient at handling large number of requests (scales better than PHP)
3.Allows both client and server side to be written in javascript

Answer 42

give 3 points that describe
node.js

Question 43

behaviour:
1.Include - will include the code if the file can be found, but omit it otherwise and continue
2.Require - if the script being inserted is missing, PHP will stop execution and report an error.

Answer 43

describe the difference in behaviour of the statements
1. include
2. require

Question 44

describe the function

phpinfo()

Answer 44

this function will output configuration information about PHP such as the version in use

Question 45

give 3 points that describe
python

Answer 45

points on this include:
1.Used by youtube and dropbox
2.Usefull for processing large data sets and scientific and statistical data
3.SQLLite is a database that is included with python

Question 46

describe the two methods for
creating an array

Answer 46

these include:
1.Using the array() function
2.Using the [] notation

Question 47

these include:

1. A constant’s value cannot be changed after it is set
2. Constant names do not need a leading dollar sign ($)
3. Constants can be accessed regardless of scope
4. Constant values can only be strings and numbers

Answer 47

what are the
4 rules governing the declaration of constant

Question 48

describe the superglobal variable
$_SERVER

Answer 48

this is an array that contains data about the server running the PHP script.

Question 49

these include:
1.A variable name always begins with a dollar character ($) followed by a letter or underscore (never a number)
2.Allowed characters in a variable name are (a-b, 1-9, _)
3.Characters are case sensitive
4.PHP is dynamically typed so we do not need to declare the data type the variable will hold

Answer 49

what are the
4 rules that govern the declaration of variables

Question 50

variations of this are:
1.extract only the value of the current element
2.Extract the key and value of the current element

Answer 50

describe the 2 variations of the PHP for each loop

Question 51

describe the function

Die()

Answer 51

this function prints a message and terminates the current script.

Question 52

how is PHP code placed inside a PHP document

Answer 52

we acieve this by using:

<?php
code
?>

Question 53

Basic Syntax (arguments ommitted):
basename(path)

@param path (Required) Specifies a file path

Answer 53

describe the syntax and paramers of

basename()

Question 54

Syntax:

while (condition is true) {
code to be executed;
}

Answer 54

what is the syntax of the PHP while loop

Question 55

name 5
server side programming languages

Answer 55

these include:
1.Hypertext Preprocessor (PHP)
2.Active Server Pages.NET (ASP.NET)
3.Java
4.Python
5.Node.js

Question 56

what are the 3 methods for commenting in PHP

Answer 56

these include:

// This is a basic one-line PHP comment
/* This is a C-style PHP comment that can span multiple lines.
Note it must be closed */
# This is a “shell-style” PHP one-line comment.

NOTE: Most likely the first two comment styles are most likely to be encountered

Question 57

describe the superglobal variable
$_FILES

Answer 57

An array that contains data about files uploaded using a special type of POST request.

Question 58

what are the
4 rules governing the declaration of constant

Answer 58

these include:

1. A constant’s value cannot be changed after it is set
2. Constant names do not need a leading dollar sign ($)
3. Constants can be accessed regardless of scope
4. Constant values can only be strings and numbers

Question 59

what is the
syntax for extracting data from an array

Answer 59

Syntax:

$arrayName[index/key]

Question 60

within a double quoted string what are the 3 ways to include a variable

Answer 60

this can be achieved using any of the following:
1. $var
2. ${var}
3. {$var}

NOTE: for readability it might be preferrable to use method 3

Question 61

describe the superglobal variable
$_SESSION

Answer 61

An array that contains data previously stored on the server in the current session

Question 62

the data is sent within a HTTP request and then made available to PHP via its superglobal variables

Answer 62

how is the HTML form data made available to a PHP script upon submition

Question 63

Syntax:
empty(variable);

@param variable (Required) Specifies the variable to check

Answer 63

describe the syntax and parameters of

empty()

Question 64

using a for each loop write the syntax for
extracting only the value of the current element

Answer 64

syntax:

foreach ($array as $value) {
    code to be executed;
}

Question 65

this function is used to define a constant

Answer 65

describe the function

define()

Question 66

these include:
1.integer 0 and float 0.0
2.the empty string “” and “0” (because it is equivalent to integer 0)
3.an empty array []
4.the null value
5.and of course, the boolean false

Answer 66

describe the 5
values that are considered
falsey

Question 67

syntax:

foreach ($array as $value) {
    code to be executed;
}

Answer 67

using a for each loop write the syntax for
extracting only the value of the current element

Question 68

Basic syntax (arguments ommitted)
htmlspecialchars(string)

@param string the string to convert

Answer 68

describe the syntax and parameters of

htmlspecialchars()

Question 69

this pattern of processing may be:
1.Generate a welcome page with a choice of tasks and send this to the user.
2.Receive back a request with data on the task to carry out. Generate a new page to respond to that request using data from the database. The full page itself never exists on the server. Only a collection of templates and data in the servers.
3.Repeat this second series of actions.

Answer 69

describe the pattern of processing that PHP might take when in a session with a user but the session is not user specific

Question 70

define
Cross site scripting (XSS)

Answer 70

this is an attack that allows a user to inject there own scripts into a website. when the website is loaded there is potential that this script could be ran on an unsuspecting users browser

Question 71

describe a typical use case for
Hypertext Preprocessor (PHP)

Answer 71

This is typically used where all or part of a web page must be dynamically created.

The data it uses to create the page will most likely be retrieved from one or more databases

Question 72

a function that converts some predefined characters to HTML entities.

Answer 72

describe the function

htmlspecialchars()

Question 73

when creating a condition in a while loop what type of tests are recommended

Answer 73

When programming loops it can be better to test a condition such as (<=, >=, <, >) rather than equality (==)

Question 74

This is typically used where all or part of a web page must be dynamically created.

The data it uses to create the page will most likely be retrieved from one or more databases

Answer 74

describe a typical use case for
Hypertext Preprocessor (PHP)

Question 75

these include:

// This is a basic one-line PHP comment
/* This is a C-style PHP comment that can span multiple lines.
Note it must be closed */
# This is a “shell-style” PHP one-line comment.

NOTE: Most likely the first two comment styles are most likely to be encountered

Answer 75

what are the 3 methods for commenting in PHP

Question 76

Syntax:
var_export(variable,return);

@param variable (Required). Specifies the variable to check
@param return (Optional). If set to true, it returns the variable representation instead
of outputting it

Answer 76

what are the syntax and parameters of

var_export()

Question 77

give 3 points about
superglobal variables

Answer 77

points include:
1.These are built in variables of PHP
2.They can be accessed from any scope
3.Each of these is an array, so can be iterated over using a for each loop or looking for a specific item using its key

Question 78

Syntax:
Die(message)

@param message (Required) A message or status number to print before terminating the script. A status number will not be written to the output, just used as the exit status.

Answer 78

describe the syntax and paramers of

die()

Question 79

describe the superglobal variable
$_COOKIE

Answer 79

An array that contains cookies sent to the server that were previously set by the same server.

Question 80

describe an
Associative arrays

Answer 80

sometimes known as a dictionary is an array with named keys and associated values for each key

Question 81

what are the
4 rules that govern the declaration of variables

Answer 81

these include:
1.A variable name always begins with a dollar character ($) followed by a letter or underscore (never a number)
2.Allowed characters in a variable name are (a-b, 1-9, _)
3.Characters are case sensitive
4.PHP is dynamically typed so we do not need to declare the data type the variable will hold

Question 82

Syntax:
unset(variable, ….);

@param variable (Required). Specifies the variable or array value to unset
@param … (Optional) Another variable to unset

Answer 82

describe the syntax and parameters of

unset()

Question 83

these include:
1. $_SERVER
2. $_GET
3. $_POST
4. $_FILES
5. $_COOKIE
6. $_SESSION

Answer 83

name 6
important superglobal variables

Question 84

this is accomplished by using the define() function

Answer 84

how do we
declare a constant in PHP

Question 85

when accessing an array what action should we perform first and why

Answer 85

when we access an array we should always check to see if it is empty.

the reason being because if we access an element that is not there then PHP will output a notice in the HTML. this should be hidden

Question 86

these include
1.Loose comparison (==) - will only check that two values are the same
2.Strict comparison (===) - will check that both the type and value are the same

Answer 86

describe the 2
methods of comparison

Question 87

the reason for this is because it is possible for a user to send any data to the server

Answer 87

why should incoming data to a server always be cleaned on the server

Question 88

Single quotes - these are interpreted exactly as written and so the text within the single quotes will always be unchanged

Double quotes - anything written within double quotes will be interpreted by PHP, this means if a variable name is included it will be evaluated and replaced by its value. Any other escape sequences will also be interpreted within double quotes

Answer 88

describe the
difference between declaring strings with single vs double quotes

Question 89

describe the 2 variations of the PHP for each loop

Answer 89

variations of this are:
1.extract only the value of the current element
2.Extract the key and value of the current element

Question 90

this function returns the filename from a path.

Answer 90

describe the function

basename()

Question 91

describe the function

empty()

Answer 91

this function checks whether a variable/array is empty or not. This function returns false if the variable exists and is not empty, otherwise it returns true.

Question 92

describe the pattern of processing that PHP might take when in a session with a specific user

Answer 92

this pattern of processing might be:
1. Generate a welcome page with forms for the user to sign in.
2. Receive the sign in, validate the data, and authenticate the user.
3. Receive data back from the user, validate the data. Identify the user from the session
4. continue step 3 untill user signs out or there is inactivity

NOTE: at steps 2 and 3 we may have further processing including accessing a database and creating unique pages for the user

Question 93

how do we perform a
not operation

Answer 93

this is achieved using the exclamation mark (!)

Question 94

why should incoming data to a server always be cleaned on the server

Answer 94

the reason for this is because it is possible for a user to send any data to the server

Question 95

how is the HTML form data made available to a PHP script upon submition

Answer 95

the data is sent within a HTTP request and then made available to PHP via its superglobal variables

Question 96

this can be achieved using any of the following:
1. $var
2. ${var}
3. {$var}

NOTE: for readability it might be preferrable to use method 3

Answer 96

within a double quoted string what are the 3 ways to include a variable

Question 97

these include:
1.Using the array() function
2.Using the [] notation

Answer 97

describe the two methods for
creating an array

Question 98

how can we dynamically include a seperate PHP file into our current PHP file

Answer 98

this can be accomplished using the statements
1. include
2. require

Question 99

Syntax:

$arrayName[index/key] = newValue;

Answer 99

what is the syntax for
updating a value in an array

Question 100

When programming loops it can be better to test a condition such as (<=, >=, <, >) rather than equality (==)

Answer 100

when creating a condition in a while loop what type of tests are recommended

Question 101

this pattern of processing might be:
1. Generate a welcome page with forms for the user to sign in.
2. Receive the sign in, validate the data, and authenticate the user.
3. Receive data back from the user, validate the data. Identify the user from the session
4. continue step 3 untill user signs out or there is inactivity

NOTE: at steps 2 and 3 we may have further processing including accessing a database and creating unique pages for the user

Answer 101

describe the pattern of processing that PHP might take when in a session with a specific user

Question 102

Syntax:

$arrayName[index/key]

Answer 102

what is the
syntax for extracting data from an array

Question 103

describe the syntax and paramers of

basename()

Answer 103

Basic Syntax (arguments ommitted):
basename(path)

@param path (Required) Specifies a file path

Question 104

describe the 2
methods of comparison

Answer 104

these include
1.Loose comparison (==) - will only check that two values are the same
2.Strict comparison (===) - will check that both the type and value are the same

Question 105

when implementing the server side of a web application name 5 items that would be required

Answer 105

for this we require:
1.infrastructure - Dedicated hardware or cloud infrastructure
2.operating system - that can interact with the hardware and run software on top of
3.Web server software - that can handle incoming and outgoing messages to the internet and interact with other server software
4.server side programming language - to handle buisness logic and data processing
5.Database software and associated hardware - so that data can be stored and retrieved

Question 106

a function that outputs or returns structured information about a variable.

Answer 106

describe the function

var_export()

Question 107

function used to unset/destroy variable and array values

Answer 107

describe the function

unset()

Question 108

describe the syntax and paramers of

die()

Answer 108

Syntax:
Die(message)

@param message (Required) A message or status number to print before terminating the script. A status number will not be written to the output, just used as the exit status.

Question 109

these include:
1.Lists - where an index number is automatically associated with a value
2.Dictianories (Associative array) - where we specify a key and a value for the element in the array

NOTE:
* each key of a dictionary must be unique
* The key of a dictionary can be an integer or string

Answer 109

describe the 2 types of arrays that can be created

Question 110

how is string concatenation performed

Answer 110

this is achieved using dot notation

example:

<?php
$mystring1 = 'The Cat';
$mystring2 = 'on the mat';
$mystring3 = 'got the cream';
$mystring4 = $mystring1 . ' ' . $mystring3;
echo "<p>$mystring4</p>";
//Output: <p>The Cat got the cream</p>
?>

Question 111

this can be accomplished by using the unset() function

Answer 111

how can we
remove an item from an array

Question 112

describe the difference in behaviour of the statements
1. include
2. require

Answer 112

behaviour:
1.Include - will include the code if the file can be found, but omit it otherwise and continue
2.Require - if the script being inserted is missing, PHP will stop execution and report an error.

Question 113

the risk of having these is that a user could potentially find there URL and execute them.

NOTE: these scripts could potentially give data away that we did not intend

Answer 113

what is the risk of having seperate PHP files that we will use via include and require

Question 114

points include:
1.These are built in variables of PHP
2.They can be accessed from any scope
3.Each of these is an array, so can be iterated over using a for each loop or looking for a specific item using its key

Answer 114

give 3 points about
superglobal variables

Question 115

describe the function

unset()

Answer 115

function used to unset/destroy variable and array values

Question 116

what is the risk of having seperate PHP files that we will use via include and require

Answer 116

the risk of having these is that a user could potentially find there URL and execute them.

NOTE: these scripts could potentially give data away that we did not intend

Question 117

give 3 points that describe
node.js

Answer 117

points on this include:
1.Provides a javascript runtime on the server
2.Efficient at handling large number of requests (scales better than PHP)
3.Allows both client and server side to be written in javascript

Question 118

this is an attack that allows a user to inject there own scripts into a website. when the website is loaded there is potential that this script could be ran on an unsuspecting users browser

Answer 118

define
Cross site scripting (XSS)

Question 119

in 4 steps describe a Cross site scripting (XSS) that
1. injects code via the comments
2. creates an alert when visitors view the website

Answer 119

Example:
1.A script tag with an alert is placed inside a comments section
2.The comment gets saved as is in the database
3.When new visitors view the comments the script tag will be pulled from the database and dynamically inserted into the html and sent to the user
4.The users browser sees the script tag in the HTML and runs the alert

NOTE: within the script tags could be any kind of malicious code

Question 120

this can be accomplished using the statements
1. include
2. require

Answer 120

how can we dynamically include a seperate PHP file into our current PHP file

Question 121

for this we require:
1.infrastructure - Dedicated hardware or cloud infrastructure
2.operating system - that can interact with the hardware and run software on top of
3.Web server software - that can handle incoming and outgoing messages to the internet and interact with other server software
4.server side programming language - to handle buisness logic and data processing
5.Database software and associated hardware - so that data can be stored and retrieved

Answer 121

when implementing the server side of a web application name 5 items that would be required

Question 122

describe the pattern of processing that PHP might take when in a session with a user but the session is not user specific

Answer 122

this pattern of processing may be:
1.Generate a welcome page with a choice of tasks and send this to the user.
2.Receive back a request with data on the task to carry out. Generate a new page to respond to that request using data from the database. The full page itself never exists on the server. Only a collection of templates and data in the servers.
3.Repeat this second series of actions.

Question 123

this is achieved using dot notation

example:

<?php
$mystring1 = 'The Cat';
$mystring2 = 'on the mat';
$mystring3 = 'got the cream';
$mystring4 = $mystring1 . ' ' . $mystring3;
echo "<p>$mystring4</p>";
//Output: <p>The Cat got the cream</p>
?>

Answer 123

how is string concatenation performed

Question 124

points on this include:
1.Open source and freely available
2.General purpose
3.but especially suited to web development because PHP can be easily embedded within HTML and can also dynamically create HTML
4.Commonly installed on apache server running linux
5.Can be installed on linux, windows and macOS

Answer 124

give 5 points that describe
Hypertext Preprocessor (PHP)

Question 125

Syntax:

if (condition) {
code to be executed if this condition is true;
} elseif (condition) {
code to be executed if first condition is false and this condition is true;
} else {
code to be executed if all conditions are false;
}

Answer 125

write out the syntax for an
if…elseif…else block

Question 126

what is the syntax for
updating a value in an array

Answer 126

Syntax:

$arrayName[index/key] = newValue;

Question 127

An array that contains data about files uploaded using a special type of POST request.

Answer 127

describe the superglobal variable
$_FILES

Question 128

give 5 points that describe
Hypertext Preprocessor (PHP)

Answer 128

points on this include:
1.Open source and freely available
2.General purpose
3.but especially suited to web development because PHP can be easily embedded within HTML and can also dynamically create HTML
4.Commonly installed on apache server running linux
5.Can be installed on linux, windows and macOS

Question 129

An array that contains cookies sent to the server that were previously set by the same server.

Answer 129

describe the superglobal variable
$_COOKIE

Question 130

this function will output configuration information about PHP such as the version in use

Answer 130

describe the function

phpinfo()

Question 131

this is achieved using the exclamation mark (!)

Answer 131

how do we perform a
not operation

Question 132

syntax:

foreach ($array as $key => $value) {
Code to execute;
}

Answer 132

using a for each loop write the syntax for extracting the key and value of the current element

Question 133

name 6
important superglobal variables

Answer 133

these include:
1. $_SERVER
2. $_GET
3. $_POST
4. $_FILES
5. $_COOKIE
6. $_SESSION

Question 134

describe the syntax and parameters of

define()

Answer 134

Basic syntax (arguments omitted):
define(name,value)

@param name (Required) Specifies the name of the constant
@param value (Required) Specifies the value of the constant.

Question 135

Example:
1.A script tag with an alert is placed inside a comments section
2.The comment gets saved as is in the database
3.When new visitors view the comments the script tag will be pulled from the database and dynamically inserted into the html and sent to the user
4.The users browser sees the script tag in the HTML and runs the alert

NOTE: within the script tags could be any kind of malicious code

Answer 135

in 4 steps describe a Cross site scripting (XSS) that
1. injects code via the comments
2. creates an alert when visitors view the website

Question 136

describe the syntax and parameters of

strcasecmp()

Answer 136

Syntax:
strcasecmp(string1,string2)

@param string1 (Required) Specifies the first string to compare
@param string2 (Required) Specifies the second string to compare