Web Development questions with verified answers
Discuss the relevance of D3 Ans✓✓✓ With big data there is more data
than can be presented reasonably using tables
D3 provides a range of techniques for visualising data.
It facilitates interaction, meaning users can tailor a visualisation for
their own needs.
It is well suited to use in a browser given its reliance on SVG
Explain CSS syntax Ans✓✓✓
Explain how you would use a CSS counter Ans✓✓✓
Explain the CSS box model Ans✓✓✓
Explain the CSS display property Ans✓✓✓ It can take the values:
none
block
inline
,inline-block (this makes the elements like inline elements but they can
have a width and height)
Explain the importance of form validation Ans✓✓✓ Important to
ensure invalid data does not reach the database
A form can validate the format of the data but not the correctness of
the data
Validation can take place on both the client and server end
Give an example of creating a bar chart using D3 Ans✓✓✓ where sun
is an array of values
How are POST messages sent Ans✓✓✓ using the HTTP headers
How can hashing be cracked Ans✓✓✓ Dictionary attack
Brute-force attack
Look-up tables
Rainbow tables
How can we break a website down from a design perspective and why
do we do this Ans✓✓✓ It can be organised into:
,The model: handles the data and business logic
The view: handle user interface application
The controller: handle user interface objects and presentation
This supports decoupling which reduces dependencies between
different components of the system
How can you access properties in JS Ans✓✓✓
How can you assign events to HTML elements Ans✓✓✓
How can you prevent cookies Ans✓✓✓ A client can inform a server
that it does not want tracking by setting the Do Not Tracker header in
the HTTP request, this is visible to the server as HTTP_DNT
How do delete a cookie Ans✓✓✓ you set its expiring time to a
negative value so it "expires"
How do sessions work, how are they stored Ans✓✓✓ The session uses
the clients cookie storage to save a key which is used to identify one
particular repository of variables
, When a session is opened on another page it scans the computer for a
user-key
If there is a match, it accesses that session, if not it starts a new session
How do web servers and browser ensure safe transfer of passwords
Ans✓✓✓ HTTPS communications using an encrypted channel (either
transport layer security (TLS) or secure sockets layer (SSL)
Server sends its digital certificate to the browser
Once the certificate is received the secure communication channel can
be established, handshaking
How do you access cookies Ans✓✓✓ Much like GET and POST you
access cookies using the $_COOKIE array indexed by the cookie names
How do you access session variables Ans✓✓✓ using the $_SESSION
array
How do you access the length of an array in java Ans✓✓✓ array.length
returns the length
Discuss the relevance of D3 Ans✓✓✓ With big data there is more data
than can be presented reasonably using tables
D3 provides a range of techniques for visualising data.
It facilitates interaction, meaning users can tailor a visualisation for
their own needs.
It is well suited to use in a browser given its reliance on SVG
Explain CSS syntax Ans✓✓✓
Explain how you would use a CSS counter Ans✓✓✓
Explain the CSS box model Ans✓✓✓
Explain the CSS display property Ans✓✓✓ It can take the values:
none
block
inline
,inline-block (this makes the elements like inline elements but they can
have a width and height)
Explain the importance of form validation Ans✓✓✓ Important to
ensure invalid data does not reach the database
A form can validate the format of the data but not the correctness of
the data
Validation can take place on both the client and server end
Give an example of creating a bar chart using D3 Ans✓✓✓ where sun
is an array of values
How are POST messages sent Ans✓✓✓ using the HTTP headers
How can hashing be cracked Ans✓✓✓ Dictionary attack
Brute-force attack
Look-up tables
Rainbow tables
How can we break a website down from a design perspective and why
do we do this Ans✓✓✓ It can be organised into:
,The model: handles the data and business logic
The view: handle user interface application
The controller: handle user interface objects and presentation
This supports decoupling which reduces dependencies between
different components of the system
How can you access properties in JS Ans✓✓✓
How can you assign events to HTML elements Ans✓✓✓
How can you prevent cookies Ans✓✓✓ A client can inform a server
that it does not want tracking by setting the Do Not Tracker header in
the HTTP request, this is visible to the server as HTTP_DNT
How do delete a cookie Ans✓✓✓ you set its expiring time to a
negative value so it "expires"
How do sessions work, how are they stored Ans✓✓✓ The session uses
the clients cookie storage to save a key which is used to identify one
particular repository of variables
, When a session is opened on another page it scans the computer for a
user-key
If there is a match, it accesses that session, if not it starts a new session
How do web servers and browser ensure safe transfer of passwords
Ans✓✓✓ HTTPS communications using an encrypted channel (either
transport layer security (TLS) or secure sockets layer (SSL)
Server sends its digital certificate to the browser
Once the certificate is received the secure communication channel can
be established, handshaking
How do you access cookies Ans✓✓✓ Much like GET and POST you
access cookies using the $_COOKIE array indexed by the cookie names
How do you access session variables Ans✓✓✓ using the $_SESSION
array
How do you access the length of an array in java Ans✓✓✓ array.length
returns the length
